file - ´y­zÀɮ׫¬ºA

(a) (b)
¡¹[cclinux1]¡¹/u/cp/89/8917026 > whereis file file: /usr/bin/file /usr/share/man/man1/file.1.gz /usr/share/man/mann/file.n.gz

¡¹[cclinux1]¡¹/u/cp/89/8917026 > ldd /usr/bin/file

libc.so.6 => /lib/libc.so.6 (0x40021000) /lib/ld-linux.so.2 => /lib/ld-linux.so.2 (0x40000000)

(c)(d)(e)(f)
·§­n¡G
file [ -bcinsvzL ] [ -f namefile ] [ -m magicfiles ] file ...

´y­z¡G

file·|¸ÕµÛ±N³o­ÓÀɮפÀÃþ¡C
//­W¤O½Ķ¤p©fµù¡G¥Îªº¬O«Ü¯«©_ªº¤èªk....¦³ÂI¬Ý¨S¦³ @@~ //¤£¹L³o¹ê¦b¬O¤@­Ó«Ü¦³½ìªºµ{¦¡ ^_^ ¨Ì§Ç¥Î¤T­Ó¤èªk¡G¤À§O¬O filesystem test, magic number test[µù4], language test¡C¥ô¦ó¤@ºØ´ú¸Õ³q¹L¡A¨º»ò³o­ÓÀɮתº«¬ºA´N¥i¥H½T©w¨ÃÅã¥Ü¥X¨Ó¡C

¨ä¤¤fileªº¤ÀÃþ¥i¯à¬O
text(¥Nªí³o¬O¤@­Ó¯Â¤å¦rÀÉ¡A¸Ì­±¥u¥]§tascii½Xªº¤å¦r¡A¨Ã¥B¥i¥Hprint¦b¿Ã¹õ¤W) executable(°õ¦æÀÉ¡A¬°UNIX©Î¨ä¥L¨t²Î½sĶ¥X¨Óªºµ{¦¡) data(¨ä¥LÀɮסA³q±`¬O¤G¶i¦ìÀɩΪ̤£¯àprint¦b¿Ã¹õ¤WªºÀÉ®×)

°Ñ¼Æ¡G

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¡¹[cclinux1]¡¹/u/cp/89/8917026/perl > file a.tar ./ /dev/hda

a.tar:	GNU tar archive
./:	directory
/dev/hda:	block special (3/0)

-b
²©ö¼Ò¦¡¡A¤£·|Åã¥Üfile name
¡¹[cclinux1]¡¹/u/cp/89/8917026 > file -b 1.txt data

-f namefile
Ū¶i¨Ó¤@­Ó¦C¥XÀɦWªºÀÉ®×(namefile)¡AµM«á¨C¦æ¤@­Ó¡A¦C¥X³o¨ÇÀɮתº«¬ºA¡C ¡¹[cclinux1]¡¹/u/cp/89/8917026/java > /bin/ls > 1.txt

¡¹[cclinux1]¡¹/u/cp/89/8917026/java > file -f 1.txt
1.txt: ASCII text
Copy.class: compiled Java class data, version 45.3
Copy.java: Java program text
Cull.java: International language text
test.txt: ASCII text
·íµM¤]¥i¥HÅý¼Ð·Ç¿é¤J(standard input, ¤@¯ë¦Ó¨¥¬OÁä½L¿é¤J)¨Ó·í°µ¿é¤J
¨Ò¦p¡A
¡¹[cclinux1]¡¹/u/cp/89/8917026/java > file -f -
test.txt #³o¦æ¬O§Ú¿é¤Jªº
test.txt: ASCII text
Copy.java #³o¦æ¤]¬O§Ú¿é¤Jªº
Copy.java: Java program text

-i
¿é¥X¬°mime type[µù1]ªºÀÉ®×¼Ò¦¡®æ¦¡ ¤ñ¦p»¡¡A¥i¯à¥Î"text/plain, ASCII"¨Ó¨ú¥N"ASCII text" ¤S¤ñ¦p»¡
#³o¬O¥­±`ªºfile°õ¦æµ²ªG
¡¹[cclinux1]¡¹/u/cp/89/8917026/perl > file test.pl test.pl: perl commands text
#¥[¤W-i¤§«áªº°õ¦æµ²ªG
¡¹[cclinux1]¡¹/u/cp/89/8917026/perl > file -i test.pl test.pl: application/x-perl
·íµM¡A­nÅýfile -i ¥i¥H¹B§@¡AÀɮתº¼Ò¦¡»Ý­n¬O¥i¥H»{±oªºµ²ºc¡C[µù3]

-m magicfiles

¸Ô²Óªº¦C¥X
-m list Specify an alternate list	of files	containing
magic numbers. This can be a single colon-separated list of files.	file, or	a

-n
Åý°õ¦æ§¹file«ü¥O¤§«á²MªÅ¿é¥X½w½Ä°Ï¡C¥i¯à¦bpipeªº®É­Ô¤~¤ñ¸û¦³¥Î¡C

-v
¿é¥Xfileªºª©¥»¤Î¸ê°T¡C
¡¹[cclinux1]¡¹/u/cp/89/8917026/perl > file -v file-3.30
magic file from /usr/share/magic

-z
°w¹ïÀ£ÁYÀɦӨ¥¡A¸ÕµÛfile¸Ì­±ªºÀÉ®× //­W¤O½Ķ¤p©fµù¡G¤£¹L§Ú¦bcclinux¤W­±¸Õ¤£¥X¨Ó¡H ¡¹[cclinux1]¡¹/u/cp/89/8917026/perl > tar -tf a.tar a.jpg
index.html
test.pl
¡¹[cclinux1]¡¹/u/cp/89/8917026/perl > file -z a.tar a.tar: GNU tar archive

-L

Åýsymlinks¤]¥i¥H¹B§@
-L option causes symlinks to be folllowed, as the
like-named option in ls(1). (on systems that sup?
port symbolic links).

-s ³q±`file¥u·|¸ÕµÛ¥hŪ¨ú¨Ã¨M©wstat«ü¥O[µù2] ªº¦^³ø¡C³o¼Ë¥i¥H¹w¨¾¦bŪ¨úÀɮתº®É­Ôµo¥Í°ÝÃD¡C¦Ó¥ [¤W-s°Ñ¼Æ¤§«á¡Afile·|Ū¨úÀɮתº¦ì¸m¤Î¨ä¥L¸ê°T¡C³o­Ó¦b¨M©wÀɮרt²Îªº®É­Ô«Ü¦³¥Î¡C³o­Ó°Ñ¼Æ¤] ·|Åýfile©R¥O©¿²¤stat©Ò´y­zªºÀɮפj¤p¡A¦]¬°¦³¨Ç¨t²Î·|¦braw disk partition[µù5] ¤§¤U´y­z¦¹¤@Àɮפ§¤j¤p¬°0¡C ½d¨Ò¡G
$ file -s /dev/hda{,1,2,3,4,5,6,7,8,9,10} /dev/hda: x86 boot sector
/dev/hda1: Linux/i386 ext2 filesystem /dev/hda2: x86 boot sector
/dev/hda3: x86 boot sector, extended partition table /dev/hda4: Linux/i386 ext2 filesystem /dev/hda5: Linux/i386 swap file /dev/hda6: Linux/i386 swap file /dev/hda7: Linux/i386 swap file /dev/hda8: Linux/i386 swap file /dev/hda9: empty
/dev/hda10: empty

[µù1] mime
MIME (Multipurpose Internet Mail Extersions)¡A ª½Ä¶¦¨ "¦h¥\¯àºô»Úºô¸ô¶l¥ó©µ®i"¡A¬°¦b¹q¸£ºô¸ô¤W¡A ª½±µ¶Ç°e¦UºØ«D¤å¦r¤º®eÀɮתººô»Úºô¸ô¼Ð·Ç¡C MIME ¼Ð·Ç±N¸ê®Æ«¬ºA¤À¬°¥D¸ê®Æ«¬ºA (primary data type) ¤Î¦¸¸ê®Æ«¬ºA (sub-type)¡C ¥D¸ê®Æ«¬ºA¦³ "text" ªí¥Ü¤å¦r¸ê®Æ
"image" ªí¥Ü¹Ï§Î¸ê®Æ
"video" ªí¥Ü°Êµe¸ê®Æ
"audio" ªí¥ÜÁn­µÀɸê®Æ
"application" ªí¥Ü°õ¦æÀɩΤG¶i¦ìÀÉ
"multipart" ¬O¥Î¥H¼Ð©ú¤º§t¦³¦h­Ó¤£¦Pªº¸ê®Æ«¬ºA "message" «h¬O«ü¤@­ÓÀɮפ¤§t¦³¥t¤@­ÓÀɮסC µ¥µ¥¡C
¦¸¸ê®Æ«¬ºA«h¬O§ó¶i¤@¨B´y­z¸ê®Æ¤º®e«¬ºA¡AÅý±µ¦¬¹q¸£¯à°÷®Ú¾Ú³o¼Ëªº°T®§¾A·íªº³B²z¡BÅã¥Ü¸ê®Æ¡C

[µù2]
¦p¡A
¡¹[cclinux1]¡¹/u/cp/89/8917026/perl > stat a.tar

[µù3]
©w¸q¦b /usr/share/magic.mime

[µù4]
©w¸q¦b /usr/share/magic

[µù5]
±q°_©lºÏ°Ï¶}©l¼g¤J(¦Ó«D±NÀÉ®×¼g¤JÀɮרt²Î)ªº¤À³Î°Ï