Lub npe
gzip, rab phom, zcat - compress lossis nthuav cov ntaub ntawv
Synopsis
gzip [ -acdfhlLnNrtvV19 ] [ -S Smi ] [ npe ... ]
gunzip [ -acfhlLnNrtvV ] [ -S Suav ] [ npe ... ]
zcat [ -fhLV ] [ npe ... ]
Kev piav qhia
Gzip thiaj li loj me me ntawm cov ntaub ntawv muaj npe siv Lempel-Ziv coding (LZ77). Thaum twg ua tau, txhua cov ntaub ntawv yog hloov los ntawm ib qho uas txuas nrog .gz , thaum uas ua tib lub tsev tswv cuab, kev nkag mus thiab kev hloov kho. Yog tias tsis muaj cov ntaub ntawv teev, lossis yog lub npe hu ua "-", qhov kev tawm tswv yim yog muab tso rau tus qauv tso zis. Gzip yuav tsuas sim ua kom cov ntaub ntawv tsis tu ncua. Nyob rau hauv kev, nws yuav tsis quav ntsej leb txuas.
Yog hais tias lub npe ntawv compressed lub npe ntev heev rau nws cov ntaub ntawv, gzip truncates nws. Gzip sim ua kom tsuas yog lub npe ntawm cov ntaub ntawv lub npe ntev tshaj 3 lub cim. (Ib feem ntawm cov npe me me.) Yog tias lub npe me me xwb, qhov tseem ceeb tshaj plaws yog qhov tseem ceeb. Piv txwv li, yog cov npe cov npe rau 14 cim, gzip.msdos.exe yog muab sau rau gzi.msd.exe.gz. Cov npe tsis muaj npe nyob rau hauv cov tshuab uas tsis muaj qhov txwv ntawm cov ntaub ntawv lub npe ntev.
Yog vim li cas, gzip yuav cia tus thawj cov ntaub ntawv lub npe thiab timestamp rau hauv cov ntaub ntawv compressed. Cov no yog siv thaum decompressing cov ntaub ntawv nrog -N xaiv. Qhov no yuav pab tau thaum lub npe ntawm cov ntaub ntawv compressed los yog thaum lub sij hawm lub sij hawm tsis tau muab khaws cia tom qab hloov ntaub ntawv.
Cov ntaub ntawv sib txuas tau tuaj yeem rov qab mus rau lawv thawj daim ntawv uas siv cov gzip -d lossis rab phom lossis zcat. Yog tias tus thawj lub npe khaws tseg rau hauv cov ntaub ntawv sau tsis yog tsim rau nws cov ntaub ntawv, lub npe tshiab yog tsim los ntawm tus thawj ib tug los mus ua kom raws txoj cai.
gunzip yuav siv ib daim ntawv teev cov ntaub ntawv rau ntawm nws cov kab hais kom ua thiab hloov txhua cov ntaub ntawv uas lub npe xaus nrog .gz, -gz, .z, -z, _z lossis .z thiab uas pib nrog tus khawv koob tseeb nrog rau cov ntaub ntawv uncompressed tsis muaj daim tseem . Gunzip kuj pom cov tshwj xeeb extensions .tgz thiab .taz li shorthands rau .tar.gz thiab .tar.Z feem. Thaum compressing, gzip siv lub .tgz extension yog tias tsim nyog siv truncating ib cov ntaub ntawv nrog ib tus neeg siv .tar extension.
gunzip tau tam sim no decompress ntaub ntawv tsim los ntawm gzip, zip, compress, compress -H los yog pob. Qhov kev paub ntawm hom ntawv tawm tswv yim tsis yog. Thaum siv thawj ob hom ntawv, rab phom pom cov tshev 32 "32" CRC. Rau ntim, rab phom zuam tshev lub sij hawm ntev zuj zus. Tus txheem compress compress yog tsis tsim los pub cov tshev mis kom sib npaug. Txawm li cas los gunzip tej zaum kuj mus ntes tau tus zauv .Z cov ntaub ntawv. Yog hais tias koj tau txais ib qho yuam kev thaum uncompressing .Z ntaub ntawv , tsis txhob xav tias cov ntaub ntawv .Z yog tseeb tsuas vim hais tias tus txheem uncompress tsis yws. Qhov no feem ntau txhais tau hais tias tus qauv uas tsis muaj kev tiv thaiv tsis xyuas nws cov tswv yim, thiab zoo siab hlo muab cov khoom pov tseg. SCO compress -H hom ntawv (jzh compression method) tsis suav nrog CRC tab sis kuj tso cai rau qee cov lus sib tw.
Cov ntaub ntawv tsim los ntawm tus zauv yuav uncompressed los ntawm gzip xwb yog tias lawv muaj ib tus neeg koom nrog cov 'deflation' method. No feature tsuas yog los pab hloov cov ntaub ntawv tar.zip rau tar.gz hom ntawv. Yuav kom zip cov ntaub ntawv nrog ob peb tug tswvcuab, siv cov ziping siv rab phom.
zcat yog zoo tib yam rau gunzip -c. (Rau tej lub systems, zcat yuav ntsia tau ua gzcat los mus khaws cia thawj qhov txuas kom hlob.) Zcat uncompresses yog ib daim ntawv teev cov ntaub ntawv ntawm kab hais kom ua los yog nws cov tswv yim tawm qauv thiab sau cov ntaub ntawv uncompressed rau cov zis txheem. zcat yuav uncompress cov ntaub ntawv uas muaj qhov tseeb tus naj npawb khauj hais tias lawv muaj ib .gz SRs los yog tsis.
Gzip siv lub Lempel-Ziv algorithm siv zip thiab PKZIP. Tus nqi ntawm kev txuam tau nyob ntawm seb qhov loj ntawm cov tswv yim thiab kev faib rau ntau hom kev nqes. Feem ntau, cov ntawv nyeem xws li qhov chaws los yog lus Askiv txo yog 60-70%. Compression feem ntau zoo dua li uas tau ua tiav los ntawm LZW (raws li siv nyob rau hauv kev sib txuas ), Huffman coding (raws li siv nyob rau hauv pob ), los yog adaptive Huffman coding ( compact ).
Compression yog ib txwm ua tau, txawm tias cov ntaub ntawv compressed yog me ntsis loj dua qub. Cov kev phem nthuav dav yog ob peb bytes rau ntawm cov ntaub ntawv gzip, ntxiv 5 bytes txhua txhua 32K block, lossis qhov nce ntawm 0.015% rau cov ntaub ntawv loj. Lus hauv no teb Nco ntsoov tias tus nab npawb ntawm cov disk siv blocks yeej tsis nce. gzip preserves hom, tswv cuab thiab timestamps ntawm cov ntaub ntawv thaum compressing los yog decompressing.
XAIV
-a -ascii
Ascii ntawv nyeem hom: hloov kev xaus-kev-siv siv cov kev cai hauv zos. Qhov kev xaiv no yog txhawb los ntawm qee cov kev cai Unix. Rau MSDOS, CR LF hloov dua siab tshiab rau LF thaum compressing, thiab LF hloov dua siab tshiab rau CR LF thaum decompressing.
-c -stdout - hauv-stdout
Sau cov zis ntawm cov zis; khaws cov ntaub ntawv tseem tsis tau hloov. Yog hais tias muaj ntau ntau cov ntaub ntawv tawm tswv yim, qhov tso zis muaj ntawm ib qho ntawm nws tus kheej ntawm cov neeg sau. Tau zoo compression, concatenate tag nrho cov ntaub ntawv cov ntaub ntawv ua ntej compressing lawv.
-d -decompress - los ua kom
Decompress.
-f-force
Quab yuam compression los yog decompression txawm tias cov ntaub ntawv muaj ntau cov kev sib txuas los yog cov ntaub ntawv coj los twb muaj, los yog cov ntaub ntawv compressed nyeem los sau ntawv rau lub davhlau ya nyob twg. Yog hais tias cov ntaub ntawv tawm tswv yim tsis nyob rau hauv ib hom ntawv lees paub los ntawm gzip, thiab yog hais tias qhov kev xaiv - tseem muaj cai, luam cov ntaub ntawv tawm yam tsis hloov mus rau tus txheej txheem kev: cia zcat coj li miv. Yog hais tias -f tsis muab, thiab thaum tsis khiav hauv keeb kwm yav dhau, gzip tuaj yeem tshawb xyuas seb puas muaj cov ntaub ntawv uas twb muaj lawm.
-h - pabcuam
Teeb ib qho kev pabcuam thiab tshem tawm.
-l --list
Rau txhua qhov ntaub ntawv sau cia, sau cov nram qab no:
compressed size: qhov loj ntawm cov ntaub ntawv compressed
uncompressed loj: me me ntawm cov ntaub ntawv uncompressed
piv: compression ratio (0.0% yog tias tsis paub)
uncompressed_name: lub npe ntawm cov ntaub ntawv uncompressed
Lub uncompressed loj yog muab raws li -1 rau cov ntaub ntawv tsis gzip hom, xws li compressed .Z ntaub ntawv. Yog xav tau qhov loj me me rau cov ntaub ntawv zoo li no, koj tuaj yeem siv tau:
zcat file.Z | wc -c
Ua ke nrog qhov kev xaiv - qhov kev xaiv, cov nram qab no yog cov nram qab no:
txoj kev: compression txujci
CRC: 32-ntsis CRC ntawm cov ntaub ntawv uas tsis muaj kev sib txuas lus
hnub tim & sijhawm: lub sijhawm thwj rau cov ntaub ntawv uas tsis zwm ua ke
Txoj kev kho kom yooj yim tam sim no yog deflate, compress, lzh (SCO compress -H) thiab pob. Tus crc yog muab ffffffff rau ib cov ntaub ntawv tsis gzip hom ntawv.
Nrog - lub npe, tus uncompressed lub npe, hnub tim thiab lub sij hawm yog cov uas muab cia hauv cov ntaub ntawv compress yog tias tam sim no.
Nrog - sib npaug, qhov sib npaug loj thiab sib txuam kom sib piv rau tag nrho cov ntaub ntawv tau tso tawm kom pom, tshwj tias qee qhov ntau thiab tsawg tsis paub. Nrog - kev xav, lub npe thiab kab ke tag nrho tsis tshwm.
-L - kab lus
Tso daim ntawv tso cai gzip thiab tso tawm.
-nws-npe-lub npe
Thaum muab ntim, tsis txhob khaws cov ntaub ntawv lub npe thiab lub sij hawm thwj thaum ua neej. (Thaum thawj lub npe yeej tau txais kev cawmdim yog tias lub npe yuav tsum tau muaj npe.) Thaum decompressing, tsis txhob xa cov ntaub ntawv lub npe yog tias tam sim no (tshem tawm tsuas yog Gzip SR tuaj rau ntawm lub npe ntim ntawv) thiab tsis thim rov qab thawj lub thwj cim (luam tawm ntawm cov ntaub ntawv compressed). Qhov kev xaiv no yog lub neej thaum thau tawm.
-N - npe
Thaum nrawm, nco ntsoov khaws cov ntaub ntawv lub npe thiab lub sij hawm stamp; qhov no yog qhov tseeb. Thaum decompressing, restore cov thawj cov ntaub ntawv lub npe thiab lub sij hawm stamp yog tias tam sim no. Qhov kev xaiv no muaj txiaj ntsig zoo nyob rau hauv lub tshuab uas muaj kev txwv ntawm cov ntaub ntawv lub npe ntev lossis thaum twg lub sijhawm stamp tau ploj tom qab hloov ntaub ntawv.
-qhia-qq -
Txhawb tag nrho cov lus ceeb toom.
-r -recursive
Taug kev cov qauv hauv kev tawm qauv. Yog hais tias ib yam ntawm cov ntaub ntawv npe teev nyob rau ntawm cov kab hais kom ua yog cov kev faib, gzip yuav nqis los rau hauv phau ntawv thiab muab tag nrho cov ntaub ntawv nws pom muaj (los yog decompress lawv nyob rau hauv cov ntaub ntawv ntawm rab phom ).
-S .suf --suffix .suf
Siv syr .suf siv .gz. Cov lus Suav tau muab rau, tiam sis cov ntawv ntxiv uas tsis yog .z thiab .gz yuav tsum raug zam kom tsis txhob muaj teeb meem thaum cov ntaub ntawv xa mus rau lwm lub tshuab. Lub npe ntxiv yuav ua rau rab phom zij zuj zus rau txhua cov ntaub ntawv tsis hais txog ntawm SRX, xws li:
gunzip -S "" * * * * rau MSDOS)
Yav dhau los ntawm gzip siv lub .z SR. Qhov no tau hloov kom tsis txhob muaj teeb meem nrog pob (1).
-t -test
Kev xeem. Kuaj xyuas cov ntaub ntawv kom ruaj ntseg.
-v- verbose
Ntsuas. Sau lub npe thiab qhov txo nqi rau txhua cov ntaub ntawv sau tawm los yog decompressed.
-V -version
Version. Muab cov zauv xov tooj thiab cov ntawv sau tso tawm ces tawm.
- # - siab - dawb
Tswj cov kev ceev ntawm kev ywj pheej uas siv cov zauv # , qhov twg - los yog - yawg qhia qhov ceev tshaj compression (tsawg zaus compression) thiab -9 los yog -best tias qhov qis compression txujci (zoo tshaj plaws compression). Lub neej yuam kev yuam kev yog -6 (uas yog, ua rau siab yuam kev ntawm kev siv nyiaj).
Kev Pab Paub Ntxiv
Cov ntaub ntawv sib txuam ntau yuav ua tau concatenated. Hauv qhov no, phom zom yuav tshem tag nrho cov tswv cuab ib zaug. Piv txwv li:
gzip-c file1> foo.gz
gzip-c file2 >> foo.gz
Ces
rab phom-f foo
yog sib npaug
miv file1 file2
Yog hais tias muaj kev puas tsuaj rau ib tug neeg ua ntaub ntawv .gz, lwm tus neeg tseem tuaj yeem tau rov qab los (yog tias tus tswv cuab raug tshem tawm). Txawm li cas los xij, koj tuaj yeem tau txais kev ywj pheej zoo dua los ntawm txhua tus tswvcuab ntim txhua zaug:
miv file1 file2 | gzip> foo.gz
compresses zoo tshaj
gzip-c file1 file2> foo.gz
Yog tias koj xav tau cov ntaub ntawv rov qab sib tw kom zoo dua, ua:
gzip -cd qub.gz | gzip> new.gz
Yog hais tias muaj ntaub ntawv compressed muaj ntau tus tswvcuab, tus zauv tsis txaus siab thiab CRC qhia los ntawm kev xaiv - xaiv siv rau tus tswvcuab kawg nkaus xwb. Yog tias koj xav tau qhov loj me me rau txhua tus tswv cuab, koj tuaj yeem siv tau:
gzip -cd file.gz | wc -c
Yog tias koj xav tsim ib qho ntaub ntawv archive nrog ntau tus tswvcuab kom cov tswvcuab muaj peevxwm yuav muab rho tawm ntawm nws tus kheej, siv ib qho chaw xws li zais lossis zip. GNU tar txhawb lub -z xaiv los ua gzip transparently. Gzip yog tsim los ua ib qho kev qhuas rau kev ua haujlwm , tsis yog hloov.
SAIB ALSO
compress (1)
Gzip cov ntaub ntawv yog teev nyob rau hauv P. Deutsch, GZIP cov ntaub ntawv hom kev qhia ua version 4.3,
Tseem ceeb: Siv tus txiv neej hais kom ua ( % tus txiv neej ) seb qhov kev hais kom raug siv hauv koj lub computer.