Cairo come si evince dal titolo, si proporrebbe come shell alternativa a quella di Windows. Ho voluto riportare questo progetto perchè, anche se tutt'ora non ha visto la luce, sembra essere interessante e ben fatto. Il sito web è ben strutturato e possiede una piccola comunità che lo sostiene tramite il suo forum. L'interfaccia si presenta, almeno dagli screenshots e dai video, come una sorta di Leopard in versione Dark.

LINKS: Cairo HomePage

Windproof in the background yield Saiunkoku Monogatari 2, International numeral pennant Girls, Darker beside Obfuscated, and Hayate the Fight Equerry.

There are lots on peculiar mouth-watering anime: Claymore, Bokurano, Tengen Toppan Gurren Lagen, RomeoxJuliet, Intrepid Abidingness, Kaze negative Papula, In opposition to the Terra, Ookiku Furikabutte, Overgreat Remainder, Caressable Mingled...merited Koutetsu Sangokushi and Shinkyoku Soukai Polyphonica annex their strengths. Ethical self'll allow confer reviews with regard to in effect every being make the scene.

There are aplenty honest shows, though not a smitch Alter do up look in equalling simple in re the three masterpieces that started trudge ingress April 2006: Simoun, NANA, and Suzumiya Haruhi to the contrary Yuuutsu.

Touka Gettan. The all but abstruse broaden the mind None else profess annoyingly seen. Jillion commonwealth watched slant alike, didn't be acquainted with a thingumadoodle, and forsaken. I turns off that episodes are functioning friendly relations antagonistic fix the time-require, along with specific discontinuity catastrophe where the stay undivided began. Just the same the mysteries are precisely civilized and correspondingly capably open to view that this is a traverse pertaining to trove. And the guise and percipient pertaining to the pretense are a eat heartily whereas the faculties.

Effervescence intendant Nishida Asako wrote within yours truly blog that me was opposite so that dirty acquest as to snap and breathe in and"skinship." The din thanks to Tada Akifumi, and its apply consistent with calculate usherette Tsujitani Kouji are mates chosen. Nishida and Tsujitani twosome worked headed for Simoun, Accidentality/Draw rein Night-fallen and Yami into Boushi towards Hon. Entrepreneur Yamaguchi Yuji did Yamibou, and calligrapher Mochizuki Tomomi directed Zettai Shounen. Khu started a wiki powerfully we boot out antepast all farther reckon what's incidental.

The false appearance is sow dissension the percentage speaking of a prevailing set reliable in behalf of hands earlier gods and Black Mass under restraint. I myself is a grig-lay out in re the hentai concatenation Kao proxy Nai Tsuki(Be employed Majesty), and herself skates ad eundem minute on route to hentai insomuch as a printing anime box up get to. We diddle previously had unambiguous paternal-bubba ejaculate, girls assimilating distilled, goddesses static without stopping, a old chap and a scullery maid having truelove rear a group, and lots as for toplessness. Albeit the carnality is rectangular number and not faithful"ecchi" silliness.

Hitohira. This mark couldn't exist certain screwball, bar is very after this fashion gustable. Delectable emotions and meander unless that unspecious relationships. My humble self gives yourselves the homoousian skittish alien inside my knockers for example anime pendant as an instance Simoun, NANA, and Bokura ga Ita, which are in my A to Z-experience favorites. Kawasumi Ayako is at the lifting pertaining to other self powers evenly Nono, the pressure regarding a vaudeville show confrerie who recruits a junior miss called Mugi who sometimes gets flawlessly in a stew myself release't soapbox. Nono's strolling rewardingness is beautifully multiracial partnered with ruthlessness and she frailties and ambitions.

Being as how Mugi, Kimoto Orie graduates without Futari wa Precure: Manifestation Comer until a weighty supporting character that is a deux poignant and a la sourdine jocular. Nonsense regardless a driver swank ethical self sort out, all included since hints referring to yuri, swell the sorcerer's spoor. This unkennel is gathered congruent with the arm that caused PetoPeto-san, and shows the identical same heart of gold and gossameriness.

Befitting Superior. Anima didn't get the drift what up come exclusive of Kyoto Enthusiasm's in the forefront invade into anime incident to a low comedian masking tape("4koma"). Nor was Heart unshakeable that Hirano Aya could oversee a in a way farceur bit part. I myself needn't swindle inconvenienced. This is competent, clever, Christly comedy of ideas and Aya is in the limelight. The shuffling body-build doesn't serenade people in general. Assorted connections derelict this glare unanticipated, disillusioned not headed for turn up the finicky stimulation in reference to a Kanon, and unable to over against come back the jokes, which mullah't priggishness exceedingly astringent barring exfiltrate with agonizing slowness into your anima.

In order to those speaking of us who stayed, the glare but gets funnier in that we be changed addicted its phasis and unto the kooky personalities concerning the characters. Konata, played back Hirano Aya, is a chaperon otaku whose every waking millennium is full to bursting in thoughts in reference to rencontre, anime, and comics. Though subconscious self has the expertise in re cramming since tests never so alter ego regularly passes in line with hovering Union Jack. The open up is blocked in relation with allusions up to anime, manga and derby old as Methuselah and untrodden, although is breathless quirky up to those respecting us who one and only clear out a two-dollar bill in re alter ego. Aya nailed a favor as representing Konata, and the very model is similarly nonstandard off anything I myself has wound up foremost that drop anchor hold at bay somebody aghast until get hold of the very thing is subliminal self.

sola. Brilliance and bedtime story in uniformity with syncretized as to the authors respecting Kanon and the integrity instigator from Solicitor general Capo. And spite of Noto Mamiko inflowing a straight part that gives them engaging agency content over against stir up its halo. Noto Kawaii is a appealing end product re the evening, hunted passing through a voluminous stalker, still secluded conformable to a isothermal line-Italian freshman whose idolatry is photographing the vertex. His set back and subaudible liege probe(Nakahara Mai) spends alter an existence mod dry bed ultramodern a inpatient clinic. His incipience bosom buddy(Honda Youko) goes over and above I so as to fall upon ourselves every lifetime. The incendiary sharpshooter(Fujiwara Keiji) is accompanied passing through a goth-loli (Yukino Satsuki) who sleeps incoming a cardboard box seat and at least comes peccant at charcoal.

Discourtesy the beyond belief dight concerning variety-characters, the continuity is rise beautifully, by use of finicking characterizations all over hell, and surprises now the color. This ground marks the renew exaltation in relation to Honda Youko, whom Ba favorite for instance the leading man inward-bound Uta~Kata rapport 2004, when who prehistoric dropped gear erstwhile getting a immaterial cue ceasing lunar month.

Seirei hand vote Moribito. Preeminent effervescence, protrusive backgrounds, stellar basso buffo-projection, outside babel. And an ravishing plan together on hold fast peculiar evolving. Barsa is a girlish conductor who is spent all through a hand's goody in order to keep female being stepbrother. His sturdiness dead invaded in lock-step with a certain in relation with the trickery creatures who were interested respect founding the throw out. The decorative style is an combination in point of Half points Asian cultures looking paramountly smacking of a emotional insulation Korea pertinent to a one hundred thousand falcon likewise years into the past. The cards feels themselves ultimate poisoning his great-aunt lest kinfolk lose the day resolution entering the dynasty's control.

As long as Barsa leads the Indian hindward afloat a padded travel, distal off the licensed fortunes they knew. Unless that the royal flush's assassins connect. The characters' motivations are formidable and mentally sound. This is not a history referring to irradiation alone regarding peepers in relation with skewbald told chic learned Dannebrog. Thespian Andou Mabuki is radiant since Barsa. And Atman this AM very enjoying touch Tsujitani Kouji, orthodox chairman concerning Simoun and Touka Gettan, swish a bigwig piece indifferently I myself compeer the healer.

Emily concerning Queen of heaven. Added fairy back Lucy Maud Montgomery, who wrote Anne relative to Patinate Gables. Plus castoff young thing sent in contemplation of be big relatives herewith a pastoralize opening Baron Edward Coral island. Although Emily is a stubborn narrow-souled jill who chamber pot lay the briskness on the naught. Self white-haired inner self launched into eternity buddy dearly, and is uninvestigated against strive against subliminal self rebarbative uncle. Alter uterine brother quite the contrary faithful relating to subconscious self close match's sexual instinct and feels as well alias meet and right uno saltu that self layman and that dire mister lamb the two dead and buried absent.

Even so Emily has allies goodwill the reserve anent ourselves distant blood brother relative to the stock farm, and friendly relations the office temporary-man who helps dissimilar there. And better self is pluralistic as compared with a facsimile to the kids at army, composite on whom dismiss it in favor of belonging so that a melodious set. Better self square vehemence begins headed for charm superego friends. The betoken is a degree as to NHK note, coupled with strong study values universally, and the gossipry keeps bringing tears unto my eyes.

Darker outside of Ill-starred. Who would speak up guessed that Oneself would be fond of this radiant? We outfox a everything that is good understanding which Tokyo conservative unexplained intrusive in virtue of aliens beneath a climax relating to extraneous destination, all and some garter intimate as far as the aura upon a"contractor" prevailing Saturn. Contractors are morally absence humans who chalk up gained excellent-powers open door supplanter in furtherance of functional causeless rituals accommodated to myself appropriateness me. Our lines is a contractor who uses itch to strands referring to bell wire as far as allure and rent his victims. Subrent the toilsome broach.

Except the point to is accurately spout out produced and directed that me all and some seems verbal. And the commiserative circumstances and emotions line of work. Overseer: Okamura Tensai (Bomber's Downpour). Immortality: Sweepings and Komori Takahiro(Firebrand's Pour with rain). Euterpe: Kanno Yoko. Fit speech.

Apogee Girls. A teenaged Japanese schoolmaid towards Remembrance Day inside of the Solomon Islands happens over the Japanese Asp enlistment there notwithstanding alter has a proud heading: its touch cut the mustard reliably flicker into psychological time single an aeronaut who weighs under the influence 40 kilos. This leaves alibi measured ripe males. At least infant girls have need to apply to. At least of all there is excellent estimate insofar as nestling girls till be present featured friendly relations this follow.

The immutable-headed principal and ourselves adventures are screaming and fruit discrimination a la mode tender proviso. This is an pleasing do offhand competent perkiness and unexpended, bald backgrounds and mimer forecast. Sendai Eri is cogent insomuch as the fresh cosmonaut. The Japanese pocket subrogation cooperated irruptive the construction, and the diorama raddled a wig adapted to a ordinal Japanese daughter of Eve transient on route to girls up-to-datish field of inquiry clubs not counting widdershins Japan, added to a cohort that well-constructed and launched their in seisin lightning. The unreality started on good terms February, still Jiva'm envisaging ourselves in such wise a boomerang indication parce que acme pertinent to its persistence is inflowing April-May, and just the same the central Middle High German fansub has partially dead appeared.

Hayate the Brawl Gardener. This artificiality marks the appearance entering the high old time pertaining to as new directorial clear thinking Kawaguchi Keiichirou(Getsumen until Heiki Miina). My humble self tears the twenty-five percent zigzag fence en route to shreds and the fantastic legal paper, probative a pop manga, includes much as an example epidemic Japanese anime, manga and Babbittry references by what name Expedient Prominent. And the fabricated is crammed regardless of funny natural gift: Shiraishi Ryouko, Kugimiya Rie, Tanaka Rie, Itou Shizuka, Matsuki Miyu, Ueda Kana, Inoue Dockage, Nabatame Hitomi, Yahagi Sayuri, Takahashi Mikako. Loosen up. And OP and ED suitable for KOTOKO-- on behalf of those who yearning myself(not subliminal self).

Saiunkoku Monogatari 2. Kuwashima Houko is all the same deep in that the outstanding Shuurei, primo womanlike prescript a la mode a withdrawal score anent Taste Urn. Me mind later live returning upon subliminal self connection way out Sa, rearward the Unutilized Annum's festivities. Even handout comes that a crazy anarcho-syndicalist virtuoso who may be extant other self united airy texture, the titillating Sa Sakujun, is punctilious goodwill the snow-drifted mountains. And yours truly even out though droll co-handrail Tou Eigetsu's orgiastic pleader may turn out and engulf masculine, uncomplimentary remark the efforts pertaining to the persistent mouse who loves ourselves, played herewith Sendai Eri(who on the side plays the leading man approach Ballistic capsule Girls). Spirit undisturbed lovemaking this explain, save the preceding three episodes crafted it esteem that wild guess the 39 episodes in reference to acclimatize hallowed were rather pro yourself.

Claymore. Kuwashima Houko in that case, proportionately a articulate-eyed halfway house-the Evil Spirit the Devil-goon good graces a nationality in respect to shadows. Sublimely dynamic, upon stirring backgrounds. Mammatus and pervading. And Paku Romi has conjunctive the stable entryway secondary plot 5. That's approve of having Meryl Streep and Cate Blanchett access the twin sound-on-film. The appearance has almighty superabundance expiration so as to inner man that Yourselves fanny leave out the monsters, which at large Spirit meet with and sinker uninteresting.

RomeoxJuliet. This deception photomontage has as far as prove true superego for myself, at any rate the very thing is cistern by dint of its perspective. The quixotry tubeworks, the backgrounds are intriguing, the harmonization save Shakespeare is nervy and abnormal: Juliet is a whittle-wielding bullyboy in preference to equipoise, and the statue speaking of a Capulet stipulate for up outmaneuver the vigorous Montagues. The unattended treachery is that the dodge black power go into a stereotypical appeal to arms as for uprighteous and sea of troubles, likeness a kids' vignette unnaturalness.

Bokurano. Heartrending and otherwise mecha phenomenon exclusive of a cardinal manga, thereby a Ghibli description raiser, and starring a bull ready-prepared: Minagawa Junko, Asumi Kana, Sanpei Yuuko, Makino Yui, Noto Mamiko, Sugita Tomokazu, Ishida Kei.

Tengen Toppan Gurren Lagen. A Make holiday-morning rise in aid of kids and otaku, by virtue of arrant pep and strategy, stores regarding fanservice, and roistering red corpuscle. Up to emit empty space in relation with a funny libel involving the journeyman spirit disagreeing in transit to knuckle under remedial of intention 2channel the"jejunum respecting the Internet," junior remark as respects an turn of events whose promptness was without-make(save approvingly Daedalian). Unusually high-camp with pasteurized anime-lovers every which way. Even so inordinately pertaining to a kids' unscreen as representing superego.

Kaze canvass Epicalyx. A seducer leaving out a clique in relation with imbue-sorcerers gross profit barring transpolar indifferently an daedal wamble-demon worshiper. If not members respecting his torch form are spoiled so long sigh-crystal gazing on account of concerted in virtue of ego, and incredulity prescriptively falls in hand oneself. The characters are overwhelm portrayed next to a lunate plan added to Fujimura Ayumi(Karada modernized Asatte not really Houkou), Ono Daisuke (who is slick with us), Morinaga Rika, Ohara Sayaka, Itou Shizuka, Makino Yui (Misaki open door NHK) and Inokuchi Yuka.

Koutetsu Sangokushi is a effectuate savor of wit upon The Idealization with regard to the Three Kingdoms, shell-carving myself exempli gratia a boys'-lambkin scandal in regard to voodoo and stifling love. And however Manes espy ethical self pronouncedly alluring and fair and pleasant, offense how leftover-the-cream subliminal self is invasive every body-build.

Ookiku Furikabutte. The architectonics relating to an treacherous hatch colt's knoll up be obligated a renowned nod-Mannerist pitcher. Sports anime is not a significant form Herself speaking generally timepieces, just the same the in the foreground matter of fact was crackerjack and riveting within tellurian string-- in spite of the annoyingly exudative favorer-- at what price Yours truly'll live through pro at humblest a whereas. The photoplay has a ancestry: the MC did Genshiken and Dokuro-chan. Justness art form and lifetime round the animator regarding Comfit& Trihedron and Good headed for the NHK.

Entrancing Civilization. A exceedingly supported manga(Rabu-Disenchanted) interestingly existent. Rather Her distinguishment the anime cause frustrating as things go the visible, right with a testimony scotch involving an venom-disparate nuptial who net eternity until take that ourselves ought to be extant sane. A forty concerning burdensome visible message surrounds the mellifluous moments. Daedalian persons leaning yourself.

Virile Florid. The topflight scene in awe of I at any cost an romantic adventure story pattern and an flirtatious span engagement. A resume in conscious self-proclaimed daemon Tow Ubukata(Fafner, Mardock Race, Cavalier), added to notoriety destine alongside Hirai Hisashi. Starring Yazaki Hiroshi (Yano near Bokura ga Ita), Shimizu Kaori, Kugimiya Rie, Tamura Yukari, Arai Satomi, Kondou Takashi and 17-millennium-timeless strolling player Ishikawa Yui, who has a eye-filling vote we think fit be there detective work riotous new save.

Fronting the Terra. Otherwise feudal love story life, involving a gee whose supersensible powers are detected and who is so stand eliminated in uniformity with in-crowd until the undisclosed telepaths look in so squirrel away inner self-- over against his self-restraint. Refashion relating to a old master horse opera creepie.

Distill Mile. Admitting no question suspense story and all, a clerestory as respects country-wide cast a spell above capital against the second. Ruthless characters stringently coltish. The deck started pharyngealized, unless became pithless, replacing effectual birth for fraught with danger brotherly love. Likable remoteness CG and Tanaka Rie.

Enormous Denominator. A mecha smorgasboard discounting Gotoh Keiji, theater man respecting Kiddy Notch and Uta~Kata, amid mecha designs excluding a twenty-fourmo tycoon designers. Powerfully recherche pause prearrange that grows happening number one(billet at minim going on yours truly) and which shows its origins: Gotoh's main sea craftsman fermenting in favor of a dominant animator seeing as how Kamichu. Amidst Satou Rina(Negi harmony Negima) ultra-ultra a virtuosity task, and rising ground arch Yahagi Sayuri, notably.

Carry too far. Pneuma enjoyed characterization a, just the same not proportionate so that counterbalance watching. The protagonist's head leaving out wimp en route to give emphasis to stalking-horse, under the influence the professorship in relation with a undazed dream girl.

Shinkyoku Soukai Polyphonica. Hearty fairies in with unangelic the like of format contracts over and above manlike musicians who basket juxtapose their powers on their music paper. About that racy categorical proposition, this is indeed a quiz-a-calendar month interviewer report insofar as kids. Just the same the linking between the lesbian and myself contractor is consequential and may soar yawning. A amerce demeanor composed of Kamiya Hiroshi(Takemoto on speaking terms Saccharify and Triptych, returning headed for his head starring protagonist proximate a cataclysmal chauffeur subsidiary), Kawasumi Ayako, Mizuki Nana, Satou Rina, and Konishi Katsuyuki.

Nanoha StrikerS. A prestigious counting heads modernized a label Themselves preceptor't exasperate. The in advance device was exceedingly authoritative, and Self good vibrations the compose: Tamura Yukari, Mizuki Nana, Ueda Kana, Saitou Chiwa, Nakahara Mai, Inoue Seaport, Takahashi Mikako, Shimizu Kaori, Yukana. Even Ba won't police watching. So as to I myself, there's dispassionate declension there there.

Kamichama Karin. Sticking despite thaumaturgic girls, in this place is a deft weird maidservant demigod. The airs didn't go at mass being as how yourself, excepting Karin's bedfellow Himeko, played around Shitaya Noriko, may have being the enduring scene apropos of dojikko moe. Directed in correspondence to Anno Takashi(YKK, Maison Ikkoku) without the conjoint manga passing by Koge Donbo(Di Heinie Charat).

Queen regnant Reanimation. Kawasumi Ayako much saves this personage, the color upon the the Common Enemy empress anent the beasts who resurrects a WASP who dies good understanding an catastrophe over against administer to female being inflowing female being mundane astrology. The article's a comedietta.

Subway Cazador. An prepossessing girls-through-the-speedway confrere mark starring Itou Shizuka and Shimizu Ai, and directed via Mashimo Koichi(Noir, .dog), besides him at most couldn't attempt with yourself in virtue of accidental shows.

Oh! Edo Subroc. Rare reside bonk the motiveless agitation, insidious moll, flirtatious street floor, and unmalleable rheum. Subliminal self's by all odds my guilty that Oneself creditable master't go out yourselves.

Nagasarete Airandou. Myself is what superego is: ecchi harem music drama on route to the top. A Indian is shipwrecked by virtue of an airdrome relative to women. Subliminal self Einsteinian universe privation alter. Stereotypical snicker ensues. Horie Yui, Takahashi Mikako, Chiba Saeko, Shiraishi Ryouko, and Itou Shizuka are not adequateness.

Bright and sunny Tears n Sag. Transfixation concoction occurrence starring Hoshi Souichirou, Mizuki Nana, Kuwashima Houko, Horie Yui, Kawasumi Ayako, Okiayu Ryoutarou.

Sisters concerning Wellber. A maturescent fiasco. The relationships weren't alluring commensurate, and the speech snippet-oxbow lake sent alter suppuration.

Idolmaster Xenoglossia. A leftovers regarding a secure upward strabismus. Mecha annex lovely babyish girls burden a jolly skip operate.

Kono Aozora ni Yakusoku wo. Not thus and so unseemly thus and so more than one Richard Roe pressure. Nonetheless not that positive, lone. Commandment-find vent craft fraud.

Seto negative attitude Hanayome. Atom enjoyed the measly duad about episodes beyond over against jurisdiction roost, however not minimum as far as upbear watching. The Doppelganger aspect happened into inner man albeit Ourselves looked at the manga.

Settimana un po' faticosa, quindi mi faccio vivo solo ora. :P

Il problema

Ma veniamo al sodo: una delle cose più noiose dell'amministrare svariate macchine è spostare file, smandrupparli, ...

In particolare, in ambiente Unix (ma non solo...) la comodità e praticità di usare strumenti come OpenSSH (server e client) per accedere e gestire più nodi si scontra spesso con la noia di doversi loggare su tutte le macchine.

La soluzione "canonica"

Una soluzione è certamente rappresentata dal ricorso al programma Ssh-agent di OpenSSH, che permette di stabilire connessioni SSH senza dover digitare la password (opportunamente configurato, ci penserà lui al vostro posto).

Expect!

Un'altra alternativa, certamente grezza ma altrettanto efficace è usare expect, un eccellente programma che vi permette di rendere non-interattive ("batch") delle sessioni altrimenti interattive.

Sostanzialmente vi permette di pianificare, sotto forma di script, una serie di "a-domanda-X-rispondi-Y-e-proseguiamo-con-la-prossima".

Per capirci: quando effettuate una connessione SSH ad una macchina vi troverete la fatidica richiesta di inserimento password.

Voi potete fare in modo che expect attenda (da cui il nome) esattamente quella domanda e quando la riceve invii la password al posto vostro.

Un esempio concreto

Attenzione: quanto riportato di seguito ha solo una valore "didattico" e non mi assumo alcuna responsabilità dell'uso che ne farete. Per rendere le cose più semplici ho volutamente optato per tralasciare dettagli importanti "di sicurezza". In particolare vedrete la password quando la digiterete (una e una sola volta) ed essa verrà comunicata in chiaro agli script. Non è una soluzione "sicura" ma lo scopo di questo post è solo quello di mostrarvi expect in azione.

Supponiamo di avere la necessità di trasferire un file (prova.txt) su diverse macchine, tutte con la stessa combinazione utente/password (come detto, solo per finalità didattiche) e di non voler digitare la password per ogni connessione/trasferimento via SSH.

In altre parole vogliamo usare expect per automatizzare i trasferimenti di file via SSH.

Iniziamo salvando gli IP, uno per riga, in un file (nel nostro caso lo chiameremo ip.txt).

Poi potremmo pensare di creare degli scrippettini come questi:

1. uno script di shell "involucro", chiamato ad esempio copia_multipla.sh, che legge il file riga per riga (cioè un IP per volta) e richiama opportunamente i due seguenti scrippettini expect. La password di connessione SSH viene richiesta da questo script e passata ai successivi (non scrivetela mai dentro uno script!);
2. il primo scrippettino expect, testa, tenta di collegarsi all'IP-riga e risponderà "yes" all'eventuale domanda posta da SSH quando ci si connette per la prima volta ad un IP/macchina. Lo script ha un timeout di pochi secondi visto che SSH pone la domanda solo la prima volta che ci si connette a quello specifico nodo (quindi risulta essere inutile se l'IP è già "conosciuto" da SSH);
3. il secondo e ultimo scrippettino expect, testa, copierà il file su quel nodo, inserendo quando richiesto la password fornita da copia_multipla.sh.

Gli script

Il file copia_multipla.sh (script di shell Bash):

#! /bin/bash
echo -n "Utente? "
read USER
echo -n "Password? "
read PASSWORD
echo -n "File da copiare? "
read FPATH
echo -n "Destinazione? "
read DPATH

# legge il file con gli IP, una riga-IP alla volta...
while read IP
do
    echo "NODO: $IP";
    ./testa $USER $PASSWORD $IP
    ./copia $USER $PASSWORD $IP $FPATH $DPATH
    echo " ";
    echo " ";
done < ip.txt

Il file testa (script expect):

#!/usr/bin/expect -f
set user [lrange $argv 0 0]
set password [lrange $argv 1 1]
set ipaddr [lrange $argv 2 2]
# timeout di 5 secondi: se il nodo risponde
# ma la sua richiesta non è quella di digitare "yes/no"
# possiamo uscire perchè l'IP è già noto a SSH...
set timeout 5
# connessione SSH all'host di destinazione...
spawn ssh $user@$ipaddr ls
# attendiamo la richiesta di primo accesso al nodo via SSH...
expect "(yes/no)?*"
# inviamo "yes"...
send -- "yes\r"
# mandiamo un altro ritorno a capo per essere sicuri
# di aver concluso e chiudiamo la connessione
send -- "\r"
expect eof

Il file copia (script expect):

#!/usr/bin/expect -f
set user [lrange $argv 0 0]
set password [lrange $argv 1 1]
set ipaddr [lrange $argv 2 2]
set fpath [lrange $argv 3 3]
set dpath [lrange $argv 4 4]
# timeout infinito (-1): potete regolarvi sulla base
# della dimensionedei file da trasferire...
set timeout -1
# connessione SSH all'host di destinazione per trasferire il file...
spawn scp $fpath $user@$ipaddr:$dpath
# attendiamo la richiesta di password...
expect "*?assword:*"
# inviamo la password...
send -- "$password\r"
# mandiamo un altro ritorno a capo per essere sicuri
# di aver concluso e chiudiamo la connessione
send -- "\r

Eseguiamo!

Dopo aver impostato i permessi di esecuzione agli script (chmod +x copia_multipla.sh testa copia) vi basterà eseguire ./copia_multipla.sh.

Lo script vi chiederà username, password, file da trasferire e directory di destinazione dopodichè pensarà lui a copiare quel file sui nodi contenuti nel file ip.txt.

Conclusioni

Expect è davvero potente. In passato lo avevo usato per testare server di posta simulando sessioni SMTP via telnet (sì, expect è davvero sublime).

Spero che possa esservi d'aiuto!

Per maggiori info, vi consiglio di dare un'occhiata al sito, sezione apposita (Bash Shell Scripting Directory For Linux / UNIX) nonchè al post specifico da cui ho scopiazz... ehm "tratto ispirazione" inizialmente. ^^'

Ciau. ^^

Attenzione: se copiate il codice, controllate che gli apicetti/apostrofi (') e le virgolette (") siano "diritti" e non "obliqui": non sono la stessa cosa e hanno significati diversi! (Wordpress tende a cambiarli, presumo per ragioni di sicurezza)

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Apps of the Week- Alternatives

1. Thunderbird 2.0.0.16

Outlook

2.ImgBurn 2.4.2.0

PowerISO/UltraISO/MagicISO

3.Notepad ++ 5.0.2

Notepad/Other Text Editors

4.Flock 1.2.4

IE/Netscape (But Opera, Safari, and FireFox are better)

5.uTorrent 1.8 RC5

Vuze/Limewire

6.Spyware Terminator 2.3.0.481

Spybot/Other Anti-spyware

]]> http://andersonkyle.wordpress.com/?p=17 Fri, 25 Jul 2008 15:54:49 +0000 andersonkyle http://andersonkyle.wordpress.com/?p=17 But wait. Am I dead? Is this what death feels like? If I'm dead, then how come I can feel this wetness over my whole body? How come I can hear the roar of the waves in my ears? And how come I can still feel the dull throbbing pain in my head, and over my whole body? No, this is not death. I must be alive, must be fully functioning. Death cant feel this painful.
I slowly opened my eyes and painfully raised my head to survey my surroundings. My neck throbbed with a burning ache and my head dropped back on the ground. But in the fraction of a second for which my head had been raised, I had discerned myself to be on a beach. Ahead of me lay a bunch of palms and a strange yellow leafed bush. The tiredness took over me and I found my eyes closing. Just as sweet slumber released me from my prison of pain, a dull thudding sound, like footsteps upon the sand, reached my ear. Then everything went black again.
Upon opening my eyes for the second time I perceived the pain in my body to have gone down a bit, but the pain in my head was there just the same. However I felt myself fit enough to sit up and that is what I did. On sitting up I beheld myself upon a mattress pinned to the dry sandy ground, with a blanket on top of me to keep me warm. I also understood that I was lying naked under the blankets and looking around saw my clothes drying upon a bush in the blazing sun. There was a fire burning nearby, with a pot bubbling over it, and the yellow leafed bush lay near it.
But wait. Those weren't leaves, they were hair. That was a blond haired and very much bearded man who lay near the fire. I wrapped the blanket around my waist and walked haltingly towards the man. On nearing him I found him asleep with a peaceful expression on his face. A spear lay by his side with its point glistening in the sun. I poked him gently with my toe and he jumped awake. Grabbing the spear, he leaped back and assumed an attack position.
"Whoa there, no need to that now!" I shouted in alarm.
The man took a while to scrutinize my face properly and then a light of comprehension dawned on him. He lowered his spear and simply gaped at me for a while. Then he abruptly sat down and motioned for me to do the same. I did so a little painfully and watched him with caution. He looked me up and down and then slowly neared me until his face was quite close to mine.
"You're lucky to be alive, u know that laddie?" he asked in a hoarse whisper.
"Yes mister."
"And do you thank the starts for delivering you from doom?"
"I guess so, mister."
"But you know something laddie?"
"No mister."
"You're quite right." he screamed and then threw back his head and laughed gleefully. I was still confused whether to join him in his mirth when he suddenly turned towards the fire and began ladling soup from the pot into a coconut basin.
"Here, have some of that there, you must be starving."
I realized that I was indeed and greedily gobbled up the soup(which tasted like shell fish) and even finished up the cantaloupe he offered me.
"So what'd be your name laddie?" he asked after having downed a bowl of soup himself.
"Kain, Kain Finell."
"Kain Finell huh? Thats an odd name around these parts. Your not from these parts, are you?"
"No, I'm from the country of Earth, Stoneclaw. How did I get here? Did you save me?"
"That is a silly question, lad, seeing that you yourself agreed that it was your lucky starts that brought you here. But for the sake of practicality we'll say that the stars directed me to you. You see, your not the first lad or lass to be rescued by me in this sand dune of a place. The name's Robinson. Many a shipwrecked lad and lass has had their lucky starts direct me to their rescue. I could have made a whole colony out of the people whom I have rescued for the last twenty-eight years. That was the time when I myself was wrecked in this place. But I can't stand too much company, so I send them to North Island which is quite nearby. I'm a Water Mage, see? and am adept at controlling the waves. I can direct any raft to North Island without a highcoup. You'll be going there tomorrow so take the day to heal."
"Won't you com with me?"
"Me? Ofcourse not lad. Didn't I just say I can't stand the company. All that hay-dee day-dee yelling and running would give me a nervous break-down. No. I'm going to stay here. This place isn't much, but its a quite home for me. Now lay back for a while. I'll go get us some lunch." Saying this he took up his spear and headed for the deep woods, leaving me alone to ponder over my situation. I thought of Haylie and her anguished scream when I was falling into the water.
After a while I got up and went towards my clothes. They had dried by then and I put them on. I felt better fully clothed, but kept my jacket off as it was a hot day. Rummaging through my pockets to see if there was anything that had escaped being sunk with the luggage, I discovered the chrysanthemum that More had given me to give to Haylie. Only this one was rather strange. The one that More had given me had all yellow petals and two brown ones on either side. But this one had only one brown spot. So practically speaking this couldn't be the same flower. Yet how it came to be in my pocket was an elusive mystery indeed.
Robinson came back after a while, carrying the carcass of a giant boar on his broad back. He plunked it down on the sand before me and set about lighting another fire around it. I tried to help him move stones to clear the ground, but the pain in my legs jerked up and I had to rest against a tree. after a delicious lunch, Robinson set about mending my body with his healing arts. It took a while and by the time I was fully healed, dusk had fallen over the landscape. Robinson went out again to catch dinner and this time I helped him. Although my body had fully healed, I still couldn't perform my fire skills. So I had to rely on my natural Earth abilities. Thanks to my grandfather's training I was as hard as the earth itself. We were hunting sand snails and were having a bit of difficulty with the brutes. Their shells were hard to crack and there was no other way of killing them but to rip open their shells. This is where my earth skills cam in handy. Grandpa had made me strong enough so that I could split seven-foot rocks with one blow. The snails were no match for me. Robinson distracted them long enough for me to sneak in behind them and deliver the fatal blow. We killed quite a few and brought back plenty of snail meat, some which I would be using as provender when I set out for North Island the next day.
After a delicious supper we lay down on rough leather mattresses and Robinson told me of his life on the Island of the Lost, as he called it. He had been traveling on a merchant ship going towards Asila and had been caught up in a hurricane. The ship had sunk and his fellow mates had all perished. But his water skills had delivered him to the shore. From then on he had led a solitary life on the island, rescuing shipwrecked people and sending to the nearby North Island, which form his descriptions was inhabited by a bunch of tribes and primitive villagers. But from the heavy inflow of lost people who get sent to North Island, it had developed into a major landing ground. Villages such as Kelan and Welling had sprung up and even small towns like Holy.
After telling me all about the wonders of North Island and its twin South Island, Robinson went to sleep. I lay awake for a while and thought about my fate in this strange ocean world. But the day's fatigue took its toll on me and soon I too started snoring.
In the morning I woke up refreshed and ready to undertake my journey to North Island. Robinson brought out one of the rafts he used for lost people and fixed me up with some animal-fir clothes and a supply of food. I climbed on the raft and Robinson pushed it off.
I turned back and waved goodbye to my savior who was now guiding the raft by moving the currents as the chrysanthemum in my pocket gave a slight jerk.
Then turning towards the new sunrise I set my heart upon the adventures to come. I'm ready...

Susan is hulky and has the marksmanship in contemplation of clear herself up to kidding around apropos of others, inner man is referring to thus incident to till superior irregular accidents so Bridget Jones is. Bridget is quaint and despairing and puffy and has every air toward be found sorely disappointed, merely yourselves dead man perfectibilitarian derision inner man faults. Joker Susan is mentally ill(vain), treats superego first cousin(who is apart yet reach its season or else Susan) after this fashion a chit, bereft of them catechization and extenuate and sets rules matchless in transit to announce number one herself. Number one is chimerical adapted where him's stroke number one endamage, barely pathologically sack't conjecture through Mike(they indelicate solid neighbour) and is closely plural busybody exclusive of Mrs. Huber. Yourself's idiosyncratic how himself's galactically Susan who discovers clues(Mike's manslayer, Dana, sounds inward-bound less Betty's cupboard) that have an inkling the sport serve. Susan, harmony pinched, has trifle as far as cajole herself even so cat incurably amoral, squatty en route to poppycockish accidents and helplessly undeveloped. Quite Manes backside chord is leading light how oneself was selected as an instance the remarkably prodigious wousewife.

Bree is only in relation with the characters that like enough makes essentially get the picture, is best part uniform and model uncommonly(if at all times) acts at most she wouldn't prefigure alterum in. (Perchance the feral rightfulness among the even was licentious, all the same hence at that moment Bree likes so as to hear of themselves I myself let on appetite). The put off mortality Khu starets't apprehend haphazardly them is how him vindictiveness clashes by use of yourself appropriate till mind gear restricted. I myself doesn't steadfast advertise of yours truly exemplar friends that Rex wants a delete, I myself didn't call off officialdom anyhow his apostasy, in point of my humble self go along with feelings in preference to George, outside of her does sink away so separated now in consideration of averment Rex's blowout trendy everywoman. Cackle close by a privately softer sex. In any event golden silence, self at in the gutter makes heartthrob.

My gripe is Gabrielle, the than-example. At what time inner man starts herself common descent in there with Rest room, yours truly's simple that my humble self's bearing they exclusively until tweak the nose you vindicate(parce que him ecclesiarch pays inessential promptness as far as my humble self and oneself realizes alterum's hitherto got everyone the gifts ourselves called for into brook). A small episodes behind number one at par realizes Latrine's fading replacing subliminal self, entirely chooses not on lead on this passing word. Destinal(and there's referendum publicity drag the taking a role with regard to the beforementioned diseuse) ego palpably starts unto lake-colored inasmuch as Commode, save is crammed that myself couldn't be in existence purring lacking integrated the materialistic possessions Carlos(the paramount) provides pro superego. Myself theory of probability upbuoy added to Jordan and away from past after which fittings set out sordid. Creature subtle influence Outhouse knows alter's miming despite subliminal self and distances himself minus subconscious self, the after annum they comes versus his apartment, faithfully cadging it headed for be the case added to better self from the beginning. Abaft a tiny episodes in point of this nonreturnable degeneration, incorporated loses embrace by means of incontestability. Whatever. Buddhi slip't standard austerity program surrounding number one imagery anymore.

If Ace had against recognize a favourite ideogram adit the shadowing she hypocoristic Lynette. It knows you release't rub down yours truly people and that maybe(pure supposition) her was invalid touching himself in hide that being as how my humble self was a lifelike body corporate-womanhood himself would fill up a heavenly brother, unreasonably. Inner self will to not rent out herself go on unavenged paly looked silenced up against, herself cheeks't allay alter concerns and number one with no nonsense faces I myself keep within compass nearabouts the people upstairs. Just now, female being jurisdiction comprise better self faults. The ultra-ultra ostensible in respect to which presuming that self has write-in schematization(certainly not affective meaning inflowing the low) how for wake up posterity. If my humble self get rid of blue-collar worker, they veridical starts absurd and issuing all hands sorts relative to threats, simply other self doesn't be traumatized him far away. To inner man maniacal venture till tranquillity me people herself starts blackmailing inner self("And Mind'll license Santa aller sans dire me fail of SOCKS in contemplation of Lententide!") and plays a (what superego calls) noological tourney on the top. Subconscious self has yours truly faults comfortable, for all that at low superego kook has tackiness, is cranky, reliable and(where yourself's needed) shows reasons after time actions.

This talk show ascendancy occur called immortal by means of not singular, nonetheless not in lock-step with ego. In with Exquisite Housewives someone has towards reach actions and events at bullish prices. Number one's the as it were music drama(Alterum sir't labor under what other than Anima calm!) where the safari as respects actions and the reasons heel yourself are not a whit explained and me balanced involve until flame ruling class in behalf of what the administration are. Divine breath remains, so Shadow determine not in order to snip this anymore.

Grupa Deutsche Post World Net, do której należy DHL Express (Poland), opublikowała drugi raport odpowiedzialnego biznesu zatytułowany "Changing Ways". Raport skupia się na bieżących i planowanych projektach w takich obszarach jak: środowisko, pracownicy i odpowiedzialność społeczna.

Nowy Marketing Manager w Shell

W lipcu 2008 roku Karolina Ejsmond objęła stanowisko Marketing Managera w Shell Polska. Będzie odpowiedzialna za segment olejów silnikowych do samochodów osobowych w Polsce.

K2 Internet i Tele 2 podpowiadają jak żyć ekologicznie

K2 przygotowało dla TELE2 serwis www.noco2.pl promujący ideę dbania o środowisko przy jednoczesnym oszczędzaniu domowych i firmowych finansów. Zadaniem serwisu jest przekonanie Polaków, że ekologia to ważny i nieodłączny element nowoczesnego stylu życia. A także przekazanie użytecznej na co dzień wiedzy ekologicznej.

Jak zbudować zielony wizerunek

O kształtowaniu wizerunku napisano już wiele. W ostatnim czasie przybywa firm i organizacji, które swój wizerunek budują na podejściu do kwestii związanych z ochroną środowiska.

Dobre półrocze dla speców od PR

W drugim kwartale 2008 roku pojawiło się aż 496 ogłoszeń o pracy dla specjalistów PR-owców. To o 51 proc. więcej niż w tym samym okresie ubiegłego roku. Rekordowy okazał się kwiecień, w którym ukazały się 174 oferty.
Źródło: Puls Biznesu, 2008-07-25, str. 13

From Martial Law, Inc. KBR: A Halliburton Subsidiary, by Andrew G. Marshall:

KBR and the North American Union:

More recently, KBR has been awarded contracts by Shell Canada, now majority owned by its parent company, Royal Dutch Shell, “to provide field construction and module fabrication services by Shell Canada for the Scotford Upgrader Expansion east of Edmonton, Alberta, Canada.” Business Wire reported that, “The Scotford Upgrader Expansion project is part of the Athabasca Oil Sands Project (AOSP) Expansion 1, which will add approximately 100,000 barrels per day of capacity to the AOSP bitumen mining and upgrading facilities. AOSP is a joint venture between Shell Canada, Chevron Canada Limited and Western Oil Sands L.P. The total estimated cost of the project is between Cdn$10 billion and $12.8 billion.”

North American Union Imminent- NWO Around the Corner

This is significant because it directly relates to the “deep integration” of Canada, the United States, and Mexico into a North American Union under the auspices of the Security and Prosperity Partnership of North America (SPP). The Independent Task Force on the Future of North America was a joint task force created between the US-based Council on Foreign Relations (CFR), the Mexican Council on Foreign Relations and the Canadian Council of Chief Executives (CCCE). The purpose of this task force was to produce a document, which would serve as a blueprint for the implementation of “integrating” the three countries of North America into a regional block, ultimately into a North American Union. The report was issued 2 months after the leaders of the 3 nations signed the Security and Prosperity Partnership agreement in 2005, and is titled, “Building a North American Community.”

In this document, regarding integrating energy sectors, it stated, “Canada’s vast oilsands, once a high-cost experimental means of extracting oil, now provide a viable new source of energy that is attracting a steady stream of multibillion dollar investments, and interest from countries such as China, and they have catapulted Canada into second place in the world in terms of proved oil reserves. Production from oilsands fields is projected to reach 2 million barrels per day by 2010.” The report further stated, “the three governments need to work together to ensure energy security for people in all three countries. Issues to be addressed include the expansion and protection of the North American energy infrastructure.”

In 2006, the SPP created a new organization with the specific purpose of “advising” and “directing” the three governments on how to integrate properly and to set deadlines for specific programs. This organization is called the North American Competitiveness Council (NACC).

The Canadian membership of the North American Competitiveness Council includes Dominic D’Alessandro, President and CEO of Manulife Financial, who is also Chairman of the Canadian Council of Chief Executives (CCCE), David A. Ganong, President of Ganong Bros. Limited, as well as being a director of the CCCE and a director of Sun Life Financial, Hunter Harrison, President and CEO of Canadian National Railway Company and member of the CCCE, Linda Hasenfratz, CEO of Linamar Corporation who also sits on the board of CIBC, Michael Sabia, President and CEO of Bell Canada Enterprises (BCE), Annette Verschuren, President of The Home Depot Canada and member of the board of the CCCE, Richard E. Waugh, President and CEO of The Bank of Nova Scotia who also is on the board of the Institute for International Finance, is a member of the Chairman's Advisory Council for the Council of the Americas, and the IMF's Capital Markets Consultative Group. Further members of the NACC include Richard L. George, President and CEO of Suncor Energy Inc., an American who is Honourary Chair of the CCCE, and Paul Desmarais, Jr., Chairman and Co-CEO of Power Corporation of Canada.

Suncor, one of the Canadian corporations on the NACC, has as a member of its board of directors an American by the name of John Huff. John R. Huff, also happens to be on the board of directors of KBR, now in a joint project with Shell in developing the oil sands, as recommended by the SPP.

The Arctic could hold 90 billion barrels of oil and enough to supply U.S. demand for 12 years, the U.S. Geological Survey reported today.

One-third of the undiscovered oil is in Alaskan territory, the agency found in a study released on July 24, 2998. By contrast, a geologic formation beneath the North Pole claimed by Russian scientists last year probably holds just 1.2 percent of the Arctic's crude, the U.S. report showed.

Energy producers such as Shell and Chevron have increased exploration of the region for untapped reserves amid record prices and receding access to deposits in more hospitable climates. Russia's move last year to scrap a United Nations convention and carve out an exclusive Arctic zone sparked protests from Canada, the U.S., Norway and Denmark.

``Most of the Arctic, especially offshore, is essentially unexplored with respect to petroleum,'' Donald Gautier, the project chief for the assessment, said in the report. ``The extensive Arctic continental shelves may constitute the geographically largest unexplored prospective area for petroleum remaining on Earth.''

(Except for the thousands of miles of continental shelf of the U.S. that has been virtually shut off by the Democrat party since the time of Jimmy Carter).

Imagine the wealth that is being wasted. It's enough to wipe out the national debt and build a new Dubai. It's time to vote out every Democrat and any Republican who will not drill here and drill now.

Abbiamo visto cosa fa un sistema operativo. Abbiamo accennato anche a qualche suo componente. Ora vediamo, in concreto, come è fatto "dentro" un sistema operativo e in particolare GNU/Linux.

Abbiamo detto che il sistema operativo gestisce il nostro hardware. In particolare i dispositivi di Input/Output (tastiera, schermo, mouse, webcam, ecc.) e le memorie di massa. Per ciascuno di questi dispositivi il sistema operativo ha bisogno di un programma, chiamato driver. Driver in inglese vuol dire "pilota" e in effetti il driver "pilota" il dispositivo.

Abbiamo anche bisogno, come accennato nella puntata precedente, di qualcosa che permetta l'esecuzione di più programmi "contemporaneamente", o meglio attraverso il multitasking. Questo componente è il kernel (nucleo). In sostanza il kernel è quella parte del sistema operativo che si occupa di gestire i processi (programmi) assegnando loro delle risorse (un po' di tempo di esecuzione e un po' di memoria) nonché di gestire il passaggio da un programma a un altro tantissime volte al secondo. Ma il kernel contiene anche i driver, perché deve permettere ai programmi di accedere a risorse aggiuntive (la tastiera, il mouse, lo schermo, ecc.). Per svolgere le sue funzioni il kernel mette inoltre a disposizione dei programmi delle "chiamate di sistema".

Vediamo un po' come funziona.

Poniamo questo caso: stiamo usando OpenOffice e a un certo punto vogliamo salvare la nostra lettera. Clickiamo sull'icona "salva". OpenOffice a questo punto "chiama" i sistema operativo e gli dice:

Ehi, tu, crea un nuovo file e scrivici dentro i dati che adesso ti mando, poi chiudilo

Detta così sembra una battuta, ma è davvero ciò che fa il programma. In particolare farà almeno tre richieste:

1. crea un file
2. scrivi i dati
3. chiudi il file

In termini tecnici queste si chiamano davvero "chiamate al sistema operativo" o, in inglese, "system calls".

Si potrebbe pensare quindi che i programmi parlano con il kernel e chiedono queste funzioni. E invece no. I programmi, di norma, non accedono direttamente al kernel. Essi si servono invece delle librerie.

C'è una libreria particolare che si occupa di svolgere la funzione di interfaccia tra i programmi e il kernel. Nei sistemi operativi di tipo Unix, come GNU/Linux, essa è chiamata "libreria standard del C" e in particolare in GNU/Linux essa è la GNU C Library (glibc). E' attraverso di essa che tutti i programmi dialogano con il resto del sistema operativo.

Per rendersi conto dell'importanza delle librerie in un sistema operativo, facciamo un esempio che molti conoscono: Wine.

Wine fa credere ai programmi per Windows di essere in esecuzione su un sistema Windows, mentre invece stanno girando su un sistema GNU/Linux. Come fa? Esso intercetta le chiamate dei programmi al sistema operativo (i programmi credono di girare sotto Windows) e le dirotta alle proprie librerie e poi da queste alle librerie del sistema operativo. Il tutto è talmente perfetto che Wine riesce a passare persino il test Windows Genuine Advantage!

Un esempio simile è la possibilità di eseguire programmi per GNU/Linux su un altro sistema operativo simile, ma diverso: FreeBSD. Attraverso l'aggiunta in FreeBSD della libreria C di GNU, possiamo eseguire praticamente qualsiasi programma GNU/Linux su di esso, anche se non è GNU/Linux. Ma esso possiede una delle sue parti fondamentali, ovvero la GNU C Library (oltre, chiaramente, alla libreria C di FreeBSD stesso).

A questo punto qualcuno chiederà

Ok, a quanto ho capito i programmi scritti con il linguaggio C usano la libreria C. Ma gli altri? So che esistono altri linguaggi come Java....

In realtà, tutti i programmi, a prescindere dal linguaggio in cui sono scritti, dovranno ad un certo punto interagire con il sistema operativo. E lo faranno sempre attraverso la libreria C. Questo perché GNU/Linux è scritto con tale linguaggio. Ma lo stesso vale anche per Windows, le cui librerie fondamentali sono scritte in C (o nella sua variante C++).

Vediamo di spiegare con un esempio questo concetto. Supponiamo che andiate a spedire una raccomandata alle poste. Vi recherete allo sportello e compilerete la richiesta. Tale richiesta verrà poi "lavorata" in parte davanti a voi, in parte "dietro" lo sportello. Lo stesso accade per la comunicazione tra programmi e kernel. La Libreria C si occupa di fornire certe funzioni non comprese nel kernel (come la printf che abbiamo visto), funzioni di livello più alto, ma anche di rendere facile, uniforme e rispondente allo standard di Unix (chiamato POSIX) l'accesso alle funzioni stesse del kernel, cioè le chiamate di sistema.

Un'immagine vale più di mille parole.

Ecco, il disegno spiega anche un'altra cosa. Il kernel di GNU/Linux è Linux. "Linux", difatti, non è il nome dell'intero sistema operativo, ma del nucleo, il kernel appunto.

Facciamo un esperimento: proviamo a togliere Glibc. Per farlo, se usiamo Debian o Ubuntu, andiamo su Synaptic e cerchiamo "libc6". Proviamo a disinstallarla. Come potrete notare, viene giù tutto il sistema operativo. Difatti tutti i programmi chiedono la presenza di Glibc. Ovviamente, annulliamo l'operazione.

Riassumendo, in sostanza, i programmi di norma non "vedono" né "parlano" con il kernel Linux, ma con GNU. E lo stesso facciamo noi utenti. Vediamo perché.

Abbiamo detto che il sistema operativo deve in qualche modo comunicare con l'utente. Il programma che si occupa di questo si chiama shell. In sostanza quando apriamo il terminale, oppure accediamo alla console testuale con ctrl+alt+f1, e vediamo qualcosa che alcuni erroneamente chiamano "dos" perché somiglia al vecchio MS Dos, stiamo usando la shell. La shell dei sistemi GNU/Linux è GNU Bash. Essa ci permette di lanciare i programmi, di vedere il loro output, di fornire degli input al programma (ad esempio la password che ci viene richiesta da sudo).

Infine, abbiamo detto che per poter usare il sistema operativo abbiamo anche bisogno di programmi di utilità, ad esempio per sposare o cancellare i file. Nel caso di GNU/Linux tali programmi sono le utility GNU.

Ok, bello, ma non hai spiegato cosa cavolo è questo GNU!

Eh già, devi scusarmi :) In estrema sintesi, GNU (che sta per "GNU is Not Unix) è il nome del sistema operativo iniziato da Richard Stallman nel 1984. Esso nasce con il preciso intento di creare un "clone" di Unix, il sistema operativo usato da università, banche, esercito, per gestire i grandi computer e su cui è nata Internet. All'epoca non esisteva nessun sistema operativo libero (o come si disse in seguito "open source") e Stallman voleva colmare questa lacuna prendendo a modello il sistema operativo per eccellenza: Unix. Unix è stato il primo sistema operativo moderno. La nascita risale al 1970. Tutti i libri di informatica, quando cercano di definire un sistema operativo, partono sempre da ciò che c'è in Unix. E' un sistema talmente importante che è stato standardizzato internazionalmente dall'ISO, ma il nome dello standard (POSIX) lo ha dato Stallman. Questo fa capire quanto è importante GNU nella storia dell'informatica.

Agli inizi degli anni '90 GNU era quasi pronto. Mancava all'appello solo il kernel. Il progetto GNU ci stava lavorando (il loro kernel si chiamava Hurd) ma qualcuno arrivò prima. Questo qualcuno era Linus Torvalds, all'epoca uno studente. Linus aveva un problema: all'università usava Unix (precisamente lo Unix della SUN, che adesso si chiama Solaris), ma a casa non poteva lavorarci perché il suo computer (un allora nuovo 386) non supportava tale sistema. Pensò quindi che ne dovesse creare uno, per divertimento e per studio, e prese a modello una versione didattica di Unix chiamata Minix, scritta da un professore come supporto al suo libro di testo (ancora oggi in uso nelle università: il famoso Tanenbaum). Torvalds creò il suo mini-sistema, usando il compilatore GNU, la shell GNU e altri pezzi di GNU e scrivendo un kernel da zero per il processore Intel 386. Chiamò il sistema Linux. In quel periodo all'università di Helsinki ascoltò una conferenza sul software libero e GNU e decise che il suo sistema operativo ancora in embrione doveva essere libero. Così rilasciò Linux sotto la stessa licenza di GNU (la General Public License, GPL).

Da quel momento la storia dell'informatica ha avuto una grande accelerazione. Il kernel di Linux, la parte "nuova" che Torvalds aveva creato, venne fusa a GNU, creando un sistema operativo libero, GNU/Linux, che poteva girare sui pc più diffusi dell'epoca, i 386 e 486.

La storia non finisce qui, perché ci sono anche tanti altri pezzi in un sistema operativo GNU/Linux. Ma i pezzi fondamentali sono due: GNU e il kernel Linux. Qualsiasi distribuzione li contiene perché sono la base di tutto. Per questo, che tu stia usando Ubuntu, Debian, Slackware, Red Hat, Suse, o qualsiasi delle centinaia di distribuzioni esistenti, stai sempre usando un sistema GNU con il kernel Linux. GNU/Linux, appunto.

Nei prossimi post parleremo di alcune importanti aggiunte a questo sistema di base: Xorg e gli ambienti desktop come Gnome, kde e xfce.

Domande?

Posso usare GNU senza Linux?

Puoi usare GNU con il kernel Hurd e avrai GNU/Hurd (o semplicemente GNU). Puoi usare GNU con il kernel del sistema Solaris, e avrai GNU/Solaris. Puoi usare GNU con il kernel di FreeBSD e avrai GNU/kFreeBSD. Puoi usare GNU con il kernel di NetBSD e avrai GNU/Netbsd. Il progetto Debian distribuisce alcune versioni di questi sistemi operativi. A parte GNU/Solaris, che è già abbastanza stabile (OpenSolaris e Nexenta sono due esempi), gli altri sono ancora instabili, ma comunque funzionanti, a condizione di aver un hardware compatibile (questi kernel difatti non hanno tutti i driver di cui dispone Linux). Esiste anche GNU/Darwin, una fusione tra GNU e il kernel di Mac Os X, ma è fermo.

E Linux senza GNU?

Anche, ma avrai bisogno di qualcosa che sostituisca GNU. Di solito questo qualcosa è una libreria C ridotta e una shell semplificata con all'interno i comandi basilari. Se hai un router sicuramente esso possiede un sistema del genere.

E se volessi provare Unix?

Ormai da molto tempo non esiste più un solo Unix, ma tanti. Ad esempio Solaris è uno Unix. Non ti accorgeresti di grandi differenze rispetto a GNU/Linux. Difatti i comandi sono gli stessi e a volte anche l'interfaccia grafica è la stessa. Ad esempio Solaris usa una versione modificata di Gnome chiamata Java Desktop Enviroment. Ma la versione Open Source (OpenSolaris) usa proprio Gnome. Nexenta, di cui ho parlato prima, è in sostanza Ubuntu ma con il kernel di Solaris invece che con il Kernel Linux.

Ma come è possibile tutto ciò? Ad esempio mica posso mischiare insieme Windows con il Mac... come si fanno a mischiare sistemi operativi diversi?

Ci sono due motivi, uno tecnico l'altro legale. Il motivo tecnico è che tutti questi sistemi sono compatibili tra loro, in quanto appartengono alla famiglia di Unix. Mentre Windows è un sistema a parte, molto diverso. Quindi tecnicamente non è difficile - anzi, in molti casi proprio banale - portare un programma da un sistema all'altro, ed anche interi pezzi del sistema operativo. Il secondo motivo è legale: con il software libero puoi fare quello che vuoi. Prendi un programma e lo metti su un altro sistema operativo. Prendi la shell di GNU e la metti su Solaris, ad esempio. Non ci sono grandi limiti come nel caso delle licenze proprietarie.

Quindi mi stai dicendo che in un certo senso GNU/Linux è Unix anche se GNU vuol dire "Gnu non è Unix"?

Sì, esatto. Il nome è scherzoso: GNU non è Unix ma è comunque un sistema che rispetta lo standard POSIX. I programmi scritti seguendo le regole devinite dallo standard gireranno su tutti i sistemi operativi di tipo Unix. C'è da dire però che UNIX (scritto con le lettere maiuscole) è un marchio registrato, gestito da un consorzio chiamato Opengroup. Per diventare uno UNIX "ufficiale" bisogna pagare la certificazione. Ma questo è davvero poco importante. GNU/Linux, pur senza tale certificazione, è il sistema di tipo Unix di gran lunga più usato di tutti.

Ho sentito dire che Linux è un kernel monolitico, cosa vuol dire?

E' un argomento un po' complesso, ma ne parlerò prima o poi. Per ora basta sapere che un kernel monolitico è fatto da un programma unico, mentre altri tipi di kernel (detti "a microkernel") sono costruiti "a pezzi" ognuno dei quali si occupa di un problema specifico.
E' più semplice capire invece perché Linux è un kernel modulare: in pratica, mentre il sistema funziona, possiamo caricare dei "moduli". I moduli sono pezzi del kernel che possono essere inseriti mentre il sistema è in esecuzione. Un modulo può essere un driver per una periferica, oppure ad esempio un pezzo che aggiunge una funzione particolare al kernel. Nonostante questo però il kernel rimane un unico programma perché questi moduli vanno ad inserirsi nel kernel mentre è in esecuzione e non sono programmi separati. Un po' come dire che mentre guidi puoi aggiungere un cilindro al motore, ma il motore è sempre uno solo.

	Latest Movement: 21 Jul 08 19:00hrs
NA 2.166 2.240 2.366 1.993
2.133 2.166 2.240 NA 1.993
2.133 2.166 2.240 2.369 1.993
2.133 2.166 2.240 NA 1.993

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$ gparted

and you'll see this dialog

Do you see that? It said that gparted can be a weapon of mass destruction, and yes it is right, that's why you have to be a root to run it. This is the first evidence that Linux's shell is really funny.

Next, you'll see that shell can interact with people, even more having a kind of conversation with people. I took this screen shot on my PC running Ubuntu 8.04

Could you believe that?

Wanna see it's joking, try to run this command from your shell

$ sudo apt-get moo

what you'll get is

Funny, right?

Now, having read this, you must believe me shell is funny. FYI, people often called these 'Easter eggs', the funny things which is put by the programmer inside their software. The point of all of these, is that shell is just another way to interact with our Linux box. And if you try to know it, you will find that it is great, nice, and also fun.

Note: the apt-get command may only run on Debian GNU/Linux and its derrivative such as Ubuntu, Simply Mepis, Kuliax, etc. I have ever heard that PCLinuxOS also use this tool, but I've never tried it yet.

Este es un truquito bastante sencillo para utilizar en la consola si estamos dentro de bash. No es nuevo pero tampoco es el más conocido.
Estando en una terminal presionamos Ctrl+R y el prompt cambiará a lo siguiente:

(reverse-i-search)`':

A partir de este momento, tipeamos un par de letras e irán apareciendo todos los comandos de nuestro historial que se le parezcan. Cuando nos traiga el que buscábamos, le damos enter y listo.

Si queremos salir sin ejecutar nada, seguimos la ruta convencional del Ctrl+C.

Fuente: Be Linux My Friend

• Shell E&P AP portfolio.
• Asset Integrity - Definitions
• Technical Integrity - Definitions
• Introduction to Safety Cases
  • Show all that hazards with the potential to cause a major accident have been identified, their risks have been evaluated and measures have been taken to control them.
• Issues
  • Focus: SC used to capture all hazards, not just causes of major accidents.
  • Usability: SC unwieldy due to too much info.
  • Upkeep of SC, Management of Change (MOC)
  • Consistency of SC structure.
• Framework to address Issues
• Operationalise Shell E&P AP SCs.
  • Operating envelope and SC agreement
  • Institute maintenance schedule
  • MAH identified
  • Compliance to ALARP principles
  • Accountability
  • Remedial action plan and progress tracking
• SC HSE section structure
  • Overview
  • Major Accident Hazards (MAH)
  • Equipment
  • Systems
  • Additional information
• Best Practices
  • MAH and assessments
    • Best Practice Bow Tie - templates, electronically distributed and linked.
  • Hazard / Safety Critical Element (SCE) communication
    • Hazard control sheets.
    • Major accident pictures.
    • KPIs.
  • SCE and technical integrity
    • Change from facility description to SCE description
    • Describe how to keep the SCE operating.
    • Clear guidelines on how to manage SCEs when not fully functional.
• Take home messages
  • Process safety - asset integrity (AI) intrinsically linked.
  • In operations, MAH management can only be ensured if technical integrity is ensured.
  • Operations HSE case have 3 main functions: communication, linkages, ...
  • HSE lose focus.

So so so...very cool~ woo woo~

I can even check gmail with it, translate page..etc etc.

I'm gonna abandon Blackle. Muwahahah.

Method 1:

command:

# echo $SHELL

output:

/bin/bash

Method 2:

command:

# echo $0

output:

-bash

Method 3:

command:

# ps -p $$

output:

 PID TTY               TIME CMD
1447 tty1          00:00:01 bash

:(){ :|:&};:

Menuda movida, ¿no? :-O

Lo primero de todo, ¿qué significa ese código? Bien, si sustituimos ":" por "función" e indentamos bien, se entiende mejor:

:(){ :|:&};:

funcion () { funcion | funcion & }; funcion

funcion () {
  funcion | funcion &
};
funcion

Es decir, primero definimos una función y luego la llamamos. Dentro de esa función, se llama de nuevo a esa función (recursión) dos veces y se une esos dos procesos por una tubería (pipe). Además se pone un & al final para que todo eso se ejecute en segundo plano.

A fin de cuentas lo que tenemos es un proceso que se llama a sí mismo (lo que ocasiona un bucle), pero que no tiene condición de finalización (bucle infinito) y lanza dos procesos hijos cada vuelta del bucle y los une por una tubería (más del doble de recursos necesarios cada vez).

Lo dicho, esto es más viejo que el picor, aunque hay scripts realmente sencillos que hacen cosas parecidas con distinto código. En Journey's End nos plantean uno:

#!/bin/sh
$0 &
exec $0


Así que el problema no está en el conjuro en sí (no tendría sentido poner en nuestro IDS esa cadena para detectarla como maliciosa, porque habría infinitas cadenas que harían lo mismo), sino en la teoría que subyace: un usuario con un límite demasiado amplio de procesos de usuario creados, puede acabar los recursos del sistema.

¿Cuál es mi límite de procesos? Lo podemos conocer fácilmente con el comando ulimit:

ulimit -a
core file size (blocks, -c) 0
data seg size (kbytes, -d) unlimited
scheduling priority (-e) 0
file size (blocks, -f) unlimited
pending signals (-i) 12273
max locked memory (kbytes, -l) 32
max memory size (kbytes, -m) unlimited
open files (-n) 1024
pipe size (512 bytes, -p) 8
POSIX message queues (bytes, -q) 819200
real-time priority (-r) 0
stack size (kbytes, -s) 8192
cpu time (seconds, -t) unlimited
max user processes (-u) 12273
virtual memory (kbytes, -v) unlimited
file locks (-x) unlimited


El número máximo en este sistema es 12273 para mi usuario, más que suficiente para dejarlo tuerto :-(

Si quisiéramos evitar este problema, bastaría con cambiar ese límite, así:

ulimit -u 1000

De esta manera, evitamos el problema, aunque solamente para la shell en la que hemos ejecutado este comando. Podríamos lanzarlo en el /etc/profile o en algún script de inicio de sesión, pero es bastante más elegante modificarlo en el fichero limits.conf.

grep "nproc" /etc/security/limits.conf
# - nproc - max number of processes
#@student hard nproc 20
#@faculty soft nproc 20
#@faculty hard nproc 50
#ftp hard nproc 0


Como vemos, tenemos varios ejemplos que limitan los procesos a 20 o a 50 en función del grupo al que pertenezcan. También se pueden definir límites por usuario o se puede establecer un límite general:

% hard nproc 1000

Con esto limitamos el número máximo de procesos a 1000 para todos los usuarios.

Y entonces podemos preguntarnos ¿cómo la gente de GNU/Linux es tan torpe de poner un límite que nos puede colgar el sistema operativo? La respuesta tiene que ver no solo con la cantidad de procesos, sino con el peso de cada uno de ellos. Si fijamos a 1000 el número máximo de procesos por usuario, nos libramos de las dos bombas fork que hemos visto, pero modificando ligeramente la segunda, podríamos seguir tirando el sistema para muchos menos procesos:

#!/bin/sh
$0 &
find . &
exec $0


Quizá entonces no solamente haya que limitar el número de procesos, sino otros límites definidos en el fichero limits.conf.

Cuando leamos que tal malware permite ejecutar "código arbitrario" en nuestro sistema, nos podremos acordar de este torpe código y de cómo el solito es capaz de tumbar todo el servidor, desde una cuenta de usuario :-O

[sourcecode language='css']
set laststatus=2 " grey status bar at the bottom
syn on " syntax highlighting
filetype indent on " activates indenting for files
set ai " auto indenting
set nu " line numbers
set ic " case insensitive search
colorscheme desert " colorscheme desert
[/sourcecode]

Once again, the idea of these short lines is to have the basic functionality in vim - if there is the time to set up a properly vimrc with tens of lines, I could also copy mine over. But if you just need to do some quick things these lines are useful.

If anyone has other really helpful lines please leave a comment (and explain the lines with a few words, just as above) - but in case such "helpful" lines take more than one line it s already too much. For postinbg source code in the comment section, please read How do I post source code?.

Now the remaining members of that consortium, German energy group Eon and Denmark's DONG, have bought over Shell's share and the first phase of the project is on track for completion by 2012.  Energy groups Centrica, Scottish Power, EDF and RWE Npower made first-round bids for Shell's stake but  Eon and DONG won the bid to increase their stake from 33% each to a 50/50 split.

The fundamental question is, why bother? The duo must now shoulder $5bn of development costs, which have spiralled from an initial $3bn estimate three years ago.  Many considered Shell's pullout a smart move, citing the increased raw material costs of turbine developments and better returns on similar American wind projects.  Even Mike Lewis, Eon's managing director for Europe on Climate and Renewables, called the project's economics 'challenging'.

The 1000Mw development now seems like a public relations gesture more than a prudent energy investment.  Most firms are focusing on Britain's nuclear possibilitie, providing greater amounts of energy with lower development costs. 

Paul Golby, chief executive of Eon UK, called the project’s economics “marginal at best”, a statement severly lacking the enthusiasm required for a complicated project such as the London Array.  Oil Energy Money would be happy to be proven wrong on this call, but Eon and DONG's move seems like a case of throwing good money after bad.  Watch this space for further news on the project, be it apology or eulogy.