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diff --git a/usr.bin/file/file.1 b/usr.bin/file/file.1 deleted file mode 100644 index c945f48dd63d..000000000000 --- a/usr.bin/file/file.1 +++ /dev/null @@ -1,588 +0,0 @@ -.\" $FreeBSD$ -.\" $Id: file.man,v 1.57 2005/08/18 15:18:22 christos Exp $ -.Dd August 18, 2005 -.Dt FILE 1 "Copyright but distributable" -.Os -.Sh NAME -.Nm file -.Nd determine file type -.Sh SYNOPSIS -.Nm -.Op Fl bchikLnNprsvz -.Op Fl f Ar namefile -.Op Fl F Ar separator -.Op Fl m Ar magicfiles -.Ar -.Nm -.Fl C -.Op Fl m Ar magicfile -.Sh DESCRIPTION -This manual page documents version 4.21 of the -.Nm -utility which tests each argument in an attempt to classify it. -There are three sets of tests, performed in this order: -file system tests, magic number tests, and language tests. -The -.Em first -test that succeeds causes the file type to be printed. -.Pp -The type printed will usually contain one of the words -.Dq Li text -(the file contains only -printing characters and a few common control -characters and is probably safe to read on an -.Tn ASCII -terminal), -.Dq Li executable -(the file contains the result of compiling a program -in a form understandable to some -.Ux -kernel or another), -or -.Dq Li data -meaning anything else (data is usually -.Sq binary -or non-printable). -Exceptions are well-known file formats (core files, tar archives) -that are known to contain binary data. -When modifying the file -.Pa /usr/share/misc/magic -or the program itself, -.Em "preserve these keywords" . -People depend on knowing that all the readable files in a directory -have the word -.Dq Li text -printed. -Do not do as Berkeley did and change -.Dq Li "shell commands text" -to -.Dq Li "shell script" . -Note that the file -.Pa /usr/share/misc/magic -is built mechanically from a large number of small files in -the subdirectory -.Pa Magdir -in the source distribution of this program. -.Pp -The file system tests are based on examining the return from a -.Xr stat 2 -system call. -The program checks to see if the file is empty, -or if it is some sort of special file. -Any known file types appropriate to the system you are running on -(sockets, symbolic links, or named pipes (FIFOs) on those systems that -implement them) -are intuited if they are defined in -the system header file -.In sys/stat.h . -.Pp -The magic number tests are used to check for files with data in -particular fixed formats. -The canonical example of this is a binary executable (compiled program) -.Pa a.out -file, whose format is defined in -.In a.out.h -and possibly -.In exec.h -in the standard include directory. -These files have a -.Sq "magic number" -stored in a particular place -near the beginning of the file that tells the -.Ux -operating system -that the file is a binary executable, and which of several types thereof. -The concept of -.Sq "magic number" -has been applied by extension to data files. -Any file with some invariant identifier at a small fixed -offset into the file can usually be described in this way. -The information identifying these files is read from the compiled -magic file -.Pa /usr/share/misc/magic.mgc , -or -.Pa /usr/share/misc/magic -if the compile file does not exist. -In addition -.Nm -will look in -.Pa $HOME/.magic.mgc , -or -.Pa $HOME/.magic -for magic entries. -.Pp -If a file does not match any of the entries in the magic file, -it is examined to see if it seems to be a text file. -ASCII, ISO-8859-x, non-ISO 8-bit extended-ASCII character sets -(such as those used on Macintosh and IBM PC systems), -UTF-8-encoded Unicode, UTF-16-encoded Unicode, and EBCDIC -character sets can be distinguished by the different -ranges and sequences of bytes that constitute printable text -in each set. -If a file passes any of these tests, its character set is reported. -ASCII, ISO-8859-x, UTF-8, and extended-ASCII files are identified -as -.Dq Li text -because they will be mostly readable on nearly any terminal; -UTF-16 and EBCDIC are only -.Dq Li "character data" -because, while -they contain text, it is text that will require translation -before it can be read. -In addition, -.Nm -will attempt to determine other characteristics of text-type files. -If the lines of a file are terminated by CR, CRLF, or NEL, instead -of the -.Ux Ns -standard -LF, this will be reported. -Files that contain embedded escape sequences or overstriking -will also be identified. -.Pp -Once -.Nm -has determined the character set used in a text-type file, -it will -attempt to determine in what language the file is written. -The language tests look for particular strings (cf -.Pa names.h ) -that can appear anywhere in the first few blocks of a file. -For example, the keyword -.Ic .br -indicates that the file is most likely a -.Xr troff 1 -input file, just as the keyword -.Ic struct -indicates a C program. -These tests are less reliable than the previous -two groups, so they are performed last. -The language test routines also test for some miscellany -(such as -.Xr tar 1 -archives). -.Pp -Any file that cannot be identified as having been written -in any of the character sets listed above is simply said to be -.Dq Li data . -.Sh OPTIONS -.Bl -tag -width indent -.It Fl b , -brief -Do not prepend filenames to output lines (brief mode). -.It Fl c , -checking-printout -Cause a checking printout of the parsed form of the magic file. -This is usually used in conjunction with -.Fl m -to debug a new magic file before installing it. -.It Fl C , -compile -Write a -.Pa magic.mgc -output file that contains a pre-parsed version of -file. -.It Fl f , -files-from Ar namefile -Read the names of the files to be examined from -.Ar namefile -(one per line) -before the argument list. -Either -.Ar namefile -or at least one filename argument must be present; -to test the standard input, use -.Dq Fl -as a filename argument. -.It Fl F , -separator Ar separator -Use the specified string as the separator between the filename and the -file result returned. -Defaults to -.Ql \&: . -.It Fl h , -no-dereference -Causes symlinks not to be followed -(on systems that support symbolic links). -This is the default if the -environment variable -.Ev POSIXLY_CORRECT -is not defined. -.It Fl i , -mime -Causes the file command to output mime type strings rather than the more -traditional human readable ones. -Thus it may say -.Dq Li "text/plain; charset=us-ascii" -rather than -.Dq Li "ASCII text" . -In order for this option to work, file changes the way -it handles files recognised by the command itself (such as many of the -text file types, directories etc), and makes use of an alternative -.Pa magic -file. -(See -.Sx FILES -section, below). -.It Fl k , -keep-going -Do not stop at the first match, keep going. -.It Fl L , -dereference -option causes symlinks to be followed, as the like-named option in -.Xr ls 1 -(on systems that support symbolic links). -This is the default if the environment variable -.Ev POSIXLY_CORRECT -is defined. -.It Fl m , -magic-file Ar list -Specify an alternate list of files containing magic numbers. -This can be a single file, or a colon-separated list of files. -If a compiled magic file is found alongside, it will be used instead. -With the -.Fl i -or -.Fl -mime -option, the program adds -.Pa .mime -to each file name. -.It Fl n , -no-buffer -Force stdout to be flushed after checking each file. -This is only useful if checking a list of files. -It is intended to be used by programs that want -filetype output from a pipe. -.It Fl N , -no-pad -Do not pad filenames so that they align in the output. -.It Fl p , -preserve-date -On systems that support -.Xr utime 3 -or -.Xr utimes 2 , -attempt to preserve the access time of files analyzed, to pretend that -.Nm -never read them. -.It Fl r , -raw -Do not translate unprintable characters to \eooo. -Normally -.Nm -translates unprintable characters to their octal representation. -.It Fl s , -special-files -Normally, -.Nm -only attempts to read and determine the type of argument files which -.Xr stat 2 -reports are ordinary files. -This prevents problems, because reading special files may have peculiar -consequences. -Specifying the -.Fl s -option causes -.Nm -to also read argument files which are block or character special files. -This is useful for determining the file system types of the data in raw -disk partitions, which are block special files. -This option also causes -.Nm -to disregard the file size as reported by -.Xr stat 2 -since on some systems it reports a zero size for raw disk partitions. -.It Fl v , -version -Print the version of the program and exit. -.It Fl z , -uncompress -Try to look inside compressed files. -.It Fl -help -Print a help message and exit. -.El -.Sh FILES -.Bl -tag -width ".Pa /usr/share/misc/magic.mime" -compact -.It Pa /usr/share/misc/magic.mgc -Default compiled list of magic numbers -.It Pa /usr/share/misc/magic -Default list of magic numbers -.It Pa /usr/share/misc/magic.mime.mgc -Default compiled list of magic numbers, used to output mime types when -the -.Fl i -option is specified. -.It Pa /usr/share/misc/magic.mime -Default list of magic numbers, used to output mime types when the -.Fl i -option is specified. -.El -.Sh ENVIRONMENT -The environment variable -.Ev MAGIC -can be used to set the default magic number file name. -If that variable is set, then -.Nm -will not attempt to open -.Pa $HOME/.magic . -.Nm -adds -.Pa .mime -and/or -.Pa .mgc -to the value of this variable as appropriate. -The environment variable -.Ev POSIXLY_CORRECT -controls (on systems that support symbolic links), if -.Nm -will attempt to follow symlinks or not. -If set, then -.Nm -follows symlink, otherwise it does not. -This is also controlled -by the -.Fl L -and -.Fl h -options. -.Sh SEE ALSO -.Xr hexdump 1 , -.Xr od 1 , -.Xr strings 1 , -.Xr magic 5 -.Sh STANDARDS CONFORMANCE -This program is believed to exceed the -.St -svid4 -of FILE(CMD), as near as one can determine from the vague language -contained therein. -Its behaviour is mostly compatible with the System V program of the same name. -This version knows more magic, however, so it will produce -different (albeit more accurate) output in many cases. -.Pp -The one significant difference -between this version and System V -is that this version treats any white space -as a delimiter, so that spaces in pattern strings must be escaped. -For example, -.Pp -.Dl ">10 string language impress\ (imPRESS data)" -.Pp -in an existing magic file would have to be changed to -.Pp -.Dl ">10 string language\e impress (imPRESS data)" -.Pp -In addition, in this version, if a pattern string contains a backslash, -it must be escaped. -For example -.Pp -.Dl "0 string \ebegindata Andrew Toolkit document" -.Pp -in an existing magic file would have to be changed to -.Pp -.Dl "0 string \e\ebegindata Andrew Toolkit document" -.Pp -SunOS releases 3.2 and later from Sun Microsystems include a -.Xr file 1 -command derived from the System V one, but with some extensions. -My version differs from Sun's only in minor ways. -It includes the extension of the -.Sq Ic & -operator, used as, -for example, -.Pp -.Dl ">16 long&0x7fffffff >0 not stripped" -.Sh MAGIC DIRECTORY -The magic file entries have been collected from various sources, -mainly USENET, and contributed by various authors. -.An Christos Zoulas -(address below) will collect additional -or corrected magic file entries. -A consolidation of magic file entries -will be distributed periodically. -.Pp -The order of entries in the magic file is significant. -Depending on what system you are using, the order that -they are put together may be incorrect. -If your old -.Nm -command uses a magic file, -keep the old magic file around for comparison purposes -(rename it to -.Pa /usr/share/misc/magic.orig ) . -.Sh EXAMPLES -.Bd -literal -$ file file.c file /dev/{wd0a,hda} -file.c: C program text -file: ELF 32-bit LSB executable, Intel 80386, version 1 (SYSV), - dynamically linked (uses shared libs), stripped -/dev/wd0a: block special (0/0) -/dev/hda: block special (3/0) -$ file -s /dev/wd0{b,d} -/dev/wd0b: data -/dev/wd0d: x86 boot sector -$ 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 - -$ file -i file.c file /dev/{wd0a,hda} -file.c: text/x-c -file: application/x-executable, dynamically linked (uses shared libs), - not stripped -/dev/hda: application/x-not-regular-file -/dev/wd0a: application/x-not-regular-file -.Ed -.Sh HISTORY -There has been a -.Nm -command in every -.Ux -since at least Research Version 4 -(man page dated November, 1973). -The System V version introduced one significant major change: -the external list of magic number types. -This slowed the program down slightly but made it a lot more flexible. -.Pp -This program, based on the System V version, -was written by -.An Ian Darwin Aq ian@darwinsys.com -without looking at anybody else's source code. -.Pp -.An John Gilmore -revised the code extensively, making it better than -the first version. -.An Geoff Collyer -found several inadequacies -and provided some magic file entries. -Contributions by the -.Sq Ic & -operator by -.An Rob McMahon Aq cudcv@warwick.ac.uk , -1989. -.Pp -.An Guy Harris Aq guy@netapp.com , -made many changes from 1993 to the present. -.Pp -Primary development and maintenance from 1990 to the present by -.An Christos Zoulas Aq christos@astron.com . -.Pp -Altered by -.An Chris Lowth Aq chris@lowth.com , -2000: -Handle the -.Fl i -option to output mime type strings and using an alternative -magic file and internal logic. -.Pp -Altered by -.An Eric Fischer Aq enf@pobox.com , -July, 2000, -to identify character codes and attempt to identify the languages -of -.No non- Ns Tn ASCII -files. -.Pp -The list of contributors to the -.Pa Magdir -directory (source for the -.Pa /usr/share/misc/magic -file) is too long to include here. -You know who you are; thank you. -.Sh LEGAL NOTICE -Copyright (c) -.An Ian F. Darwin , -Toronto, Canada, 1986-1999. -Covered by the standard Berkeley Software Distribution copyright; see the file -.Pa LEGAL.NOTICE -in the source distribution. -.Pp -The files -.Pa tar.h -and -.Pa is_tar.c -were written by -.An John Gilmore -from his public-domain -.Nm tar -program, and are not covered by the above license. -.Sh BUGS -There must be a better way to automate the construction of the -.Pa Magic -file from all the glop in -.Pa Magdir . -What is it? -Better yet, the magic file should be compiled into binary (say, -.Xr ndbm 3 -or, better yet, fixed-length -.Tn ASCII -strings for use in heterogenous network environments) for faster startup. -Then the program would run as fast as the Version 7 program of the same name, -with the flexibility of the System V version. -.Pp -The -.Nm -utility uses several algorithms that favor speed over accuracy, -thus it can be misled about the contents of -text -files. -.Pp -The support for -text -files (primarily for programming languages) -is simplistic, inefficient and requires recompilation to update. -.Pp -There should be an -.Ic else -clause to follow a series of continuation lines. -.Pp -The magic file and keywords should have regular expression support. -Their use of -.Tn "ASCII TAB" -as a field delimiter is ugly and makes -it hard to edit the files, but is entrenched. -.Pp -It might be advisable to allow upper-case letters in keywords -for e.g., -.Xr troff 1 -commands vs man page macros. -Regular expression support would make this easy. -.Pp -The program does not grok -.Tn FORTRAN . -It should be able to figure -.Tn FORTRAN -by seeing some keywords which -appear indented at the start of line. -Regular expression support would make this easy. -.Pp -The list of keywords in -.Pa ascmagic -probably belongs in the -.Pa Magic -file. -This could be done by using some keyword like -.Sq Ic * -for the offset value. -.Pp -Another optimisation would be to sort -the magic file so that we can just run down all the -tests for the first byte, first word, first long, etc, once we -have fetched it. -Complain about conflicts in the magic file entries. -Make a rule that the magic entries sort based on file offset rather -than position within the magic file? -.Pp -The program should provide a way to give an estimate -of -.Dq how good -a guess is. -We end up removing guesses (e.g.\& -.Dq Li "From " -as first 5 chars of file) because -they are not as good as other guesses (e.g.\& -.Dq Li "Newsgroups:" -versus -.Dq Li "Return-Path:" ) . -Still, if the others do not pan out, it should be possible to use the -first guess. -.Pp -This program is slower than some vendors' file commands. -The new support for multiple character codes makes it even slower. -.Pp -This manual page, and particularly this section, is too long. -.Sh AVAILABILITY -You can obtain the original author's latest version by anonymous FTP -on -.Pa ftp.astron.com -in the directory -.Pa /pub/file/file-X.YZ.tar.gz |