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FILE(1)                DragonFly General Commands Manual               FILE(1)


file - determine file type


file [-bcdEhiklLNnprsSvzZ0] [--apple] [--exclude-quiet] [--extension] [--mime-encoding] [--mime-type] [-e testname] [-F separator] [-f namefile] [-m magicfiles] [-P name=value] file ... file -C [-m magicfiles] file [--help]


This manual page documents version 5.40 of the file command. file tests each argument in an attempt to classify it. There are three sets of tests, performed in this order: filesystem tests, magic tests, and language tests. The first test that succeeds causes the file type to be printed. The type printed will usually contain one of the words text (the file contains only printing characters and a few common control characters and is probably safe to read on an ASCII terminal), executable (the file contains the result of compiling a program in a form understandable to some UNIX kernel or another), or data meaning anything else (data is usually "binary" or non-printable). Exceptions are well-known file formats (core files, tar archives) that are known to contain binary data. When modifying magic files or the program itself, make sure to preserve these keywords. Users depend on knowing that all the readable files in a directory have the word "text" printed. Don't do as Berkeley did and change "shell commands text" to "shell script". The filesystem tests are based on examining the return from a stat(2) system call. The program checks to see if the file is empty, or if it's 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 <sys/stat.h>. The magic tests are used to check for files with data in particular fixed formats. The canonical example of this is a binary executable (compiled program) a.out file, whose format is defined in <elf.h>, <a.out.h> and possibly <exec.h> in the standard include directory. These files have a "magic number" stored in a particular place near the beginning of the file that tells the UNIX operating system that the file is a binary executable, and which of several types thereof. The concept of a "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 /usr/share/misc/magic.mgc, or the files in the directory /usr/share/misc/magic if the compiled file does not exist. In addition, if $HOME/.magic.mgc or $HOME/.magic exists, it will be used in preference to the system magic files. 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 "text" because they will be mostly readable on nearly any terminal; UTF-16 and EBCDIC are only "character data" because, while they contain text, it is text that will require translation before it can be read. In addition, file 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 Unix-standard LF, this will be reported. Files that contain embedded escape sequences or overstriking will also be identified. Once file 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. <names.h>) that can appear anywhere in the first few blocks of a file. For example, the keyword .br indicates that the file is most likely a troff(1) input file, just as the keyword 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 tar(1) archives, JSON files). Any file that cannot be identified as having been written in any of the character sets listed above is simply said to be "data".


--apple Causes the file command to output the file type and creator code as used by older MacOS versions. The code consists of eight letters, the first describing the file type, the latter the creator. This option works properly only for file formats that have the apple-style output defined. -b, --brief Do not prepend filenames to output lines (brief mode). -C, --compile Write a magic.mgc output file that contains a pre-parsed version of the magic file or directory. -c, --checking-printout Cause a checking printout of the parsed form of the magic file. This is usually used in conjunction with the -m option to debug a new magic file before installing it. -d Prints internal debugging information to stderr. -E On filesystem errors (file not found etc), instead of handling the error as regular output as POSIX mandates and keep going, issue an error message and exit. -e, --exclude testname Exclude the test named in testname from the list of tests made to determine the file type. Valid test names are: apptype EMX application type (only on EMX). ascii Various types of text files (this test will try to guess the text encoding, irrespective of the setting of the `encoding' option). encoding Different text encodings for soft magic tests. tokens Ignored for backwards compatibility. cdf Prints details of Compound Document Files. compress Checks for, and looks inside, compressed files. csv Checks Comma Separated Value files. elf Prints ELF file details, provided soft magic tests are enabled and the elf magic is found. json Examines JSON (RFC-7159) files by parsing them for compliance. soft Consults magic files. tar Examines tar files by verifying the checksum of the 512 byte tar header. Excluding this test can provide more detailed content description by using the soft magic method. text A synonym for `ascii'. --exclude-quiet Like --exclude but ignore tests that file does not know about. This is intended for compatibility with older versions of file. --extension Print a slash-separated list of valid extensions for the file type found. -F, --separator separator Use the specified string as the separator between the filename and the file result returned. Defaults to `:'. -f, --files-from namefile Read the names of the files to be examined from namefile (one per line) before the argument list. Either namefile or at least one filename argument must be present; to test the standard input, use `-' as a filename argument. Please note that namefile is unwrapped and the enclosed filenames are processed when this option is encountered and before any further options processing is done. This allows one to process multiple lists of files with different command line arguments on the same file invocation. Thus if you want to set the delimiter, you need to do it before you specify the list of files, like: "-F @ -f namefile", instead of: "-f namefile -F @". -h, --no-dereference This option causes symlinks not to be followed (on systems that support symbolic links). This is the default if the environment variable POSIXLY_CORRECT is not defined. -i, --mime Causes the file command to output mime type strings rather than the more traditional human readable ones. Thus it may say `text/plain; charset=us-ascii' rather than "ASCII text". --mime-type, --mime-encoding Like -i, but print only the specified element(s). -k, --keep-going Don't stop at the first match, keep going. Subsequent matches will be have the string `\012- ' prepended. (If you want a newline, see the -r option.) The magic pattern with the highest strength (see the -l option) comes first. -l, --list Shows a list of patterns and their strength sorted descending by magic(5) strength which is used for the matching (see also the -k option). -L, --dereference This option causes symlinks to be followed, as the like-named option in ls(1) (on systems that support symbolic links). This is the default if the environment variable POSIXLY_CORRECT is defined. -m, --magic-file magicfiles Specify an alternate list of files and directories containing magic. This can be a single item, or a colon-separated list. If a compiled magic file is found alongside a file or directory, it will be used instead. -N, --no-pad Don't pad filenames so that they align in the output. -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. -p, --preserve-date On systems that support utime(3) or utimes(2), attempt to preserve the access time of files analyzed, to pretend that file never read them. -P, --parameter name=value Set various parameter limits. Name Default Explanation bytes 1048576 max number of bytes to read from file elf_notes 256 max ELF notes processed elf_phnum 2048 max ELF program sections processed elf_shnum 32768 max ELF sections processed encoding 65536 max number of bytes to scan for encoding evaluation indir 50 recursion limit for indirect magic name 50 use count limit for name/use magic regex 8192 length limit for regex searches -r, --raw Don't translate unprintable characters to \ooo. Normally file translates unprintable characters to their octal representation. -s, --special-files Normally, file only attempts to read and determine the type of argument files which stat(2) reports are ordinary files. This prevents problems, because reading special files may have peculiar consequences. Specifying the -s option causes file to also read argument files which are block or character special files. This is useful for determining the filesystem types of the data in raw disk partitions, which are block special files. This option also causes file to disregard the file size as reported by stat(2) since on some systems it reports a zero size for raw disk partitions. -S, --no-sandbox On systems where libseccomp (https://github.com/seccomp/libseccomp) is available, the -S option disables sandboxing which is enabled by default. This option is needed for file to execute external decompressing programs, i.e. when the -z option is specified and the built-in decompressors are not available. On systems where sandboxing is not available, this option has no effect. -v, --version Print the version of the program and exit. -z, --uncompress Try to look inside compressed files. -Z, --uncompress-noreport Try to look inside compressed files, but report information about the contents only not the compression. -0, --print0 Output a null character `\0' after the end of the filename. Nice to cut(1) the output. This does not affect the separator, which is still printed. If this option is repeated more than once, then file prints just the filename followed by a NUL followed by the description (or ERROR: text) followed by a second NUL for each entry. --help Print a help message and exit.


The environment variable MAGIC can be used to set the default magic file name. If that variable is set, then file will not attempt to open $HOME/.magic. file adds ".mgc" to the value of this variable as appropriate. The environment variable POSIXLY_CORRECT controls (on systems that support symbolic links), whether file will attempt to follow symlinks or not. If set, then file follows symlink, otherwise it does not. This is also controlled by the -L and -h options.


/usr/share/misc/magic.mgc Default compiled list of magic. /usr/share/misc/magic Directory containing default magic files.


file will exit with 0 if the operation was successful or >0 if an error was encountered. The following errors cause diagnostic messages, but don't affect the program exit code (as POSIX requires), unless -E is specified: * A file cannot be found * There is no permission to read a file * The file type cannot be determined


$ 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 /dev/hda: application/x-not-regular-file /dev/wd0a: application/x-not-regular-file


hexdump(1), od(1), strings(1), magic(5)


This program is believed to exceed the System V Interface Definition of FILE(CMD), as near as one can determine from the vague language contained therein. Its behavior 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. 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, >10 string language impress (imPRESS data) in an existing magic file would have to be changed to >10 string language\ impress (imPRESS data) In addition, in this version, if a pattern string contains a backslash, it must be escaped. For example 0 string \begindata Andrew Toolkit document in an existing magic file would have to be changed to 0 string \\begindata Andrew Toolkit document SunOS releases 3.2 and later from Sun Microsystems include a file command derived from the System V one, but with some extensions. This version differs from Sun's only in minor ways. It includes the extension of the `&' operator, used as, for example, >16 long&0x7fffffff >0 not stripped


On systems where libseccomp (https://github.com/seccomp/libseccomp) is available, file is enforces limiting system calls to only the ones necessary for the operation of the program. This enforcement does not provide any security benefit when file is asked to decompress input files running external programs with the -z option. To enable execution of external decompressors, one needs to disable sandboxing using the -S option.


The magic file entries have been collected from various sources, mainly USENET, and contributed by various authors. Christos Zoulas (address below) will collect additional or corrected magic file entries. A consolidation of magic file entries will be distributed periodically. 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 file command uses a magic file, keep the old magic file around for comparison purposes (rename it to /usr/share/misc/magic.orig).


There has been a file command in every UNIX 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 types. This slowed the program down slightly but made it a lot more flexible. This program, based on the System V version, was written by Ian Darwin <ian@darwinsys.com> without looking at anybody else's source code. John Gilmore revised the code extensively, making it better than the first version. Geoff Collyer found several inadequacies and provided some magic file entries. Contributions of the `&' operator by Rob McMahon, <cudcv@warwick.ac.uk>, 1989. Guy Harris, <guy@netapp.com>, made many changes from 1993 to the present. Primary development and maintenance from 1990 to the present by Christos Zoulas <christos@astron.com>. Altered by Chris Lowth <chris@lowth.com>, 2000: handle the -i option to output mime type strings, using an alternative magic file and internal logic. Altered by Eric Fischer <enf@pobox.com>, July, 2000, to identify character codes and attempt to identify the languages of non-ASCII files. Altered by Reuben Thomas <rrt@sc3d.org>, 2007-2011, to improve MIME support, merge MIME and non-MIME magic, support directories as well as files of magic, apply many bug fixes, update and fix a lot of magic, improve the build system, improve the documentation, and rewrite the Python bindings in pure Python. The list of contributors to the `magic' directory (magic files) is too long to include here. You know who you are; thank you. Many contributors are listed in the source files.


Copyright (c) Ian F. Darwin, Toronto, Canada, 1986-1999. Covered by the standard Berkeley Software Distribution copyright; see the file COPYING in the source distribution. The files tar.h and is_tar.c were written by John Gilmore from his public-domain tar(1) program, and are not covered by the above license.


Please report bugs and send patches to the bug tracker at https://bugs.astron.com/ or the mailing list at <file@astron.com> (visit https://mailman.astron.com/mailman/listinfo/file first to subscribe).


Fix output so that tests for MIME and APPLE flags are not needed all over the place, and actual output is only done in one place. This needs a design. Suggestion: push possible outputs on to a list, then pick the last-pushed (most specific, one hopes) value at the end, or use a default if the list is empty. This should not slow down evaluation. The handling of MAGIC_CONTINUE and printing \012- between entries is clumsy and complicated; refactor and centralize. Some of the encoding logic is hard-coded in encoding.c and can be moved to the magic files if we had a !:charset annotation. Continue to squash all magic bugs. See Debian BTS for a good source. Store arbitrarily long strings, for example for %s patterns, so that they can be printed out. Fixes Debian bug #271672. This can be done by allocating strings in a string pool, storing the string pool at the end of the magic file and converting all the string pointers to relative offsets from the string pool. Add syntax for relative offsets after current level (Debian bug #466037). Make file -ki work, i.e. give multiple MIME types. Add a zip library so we can peek inside Office2007 documents to print more details about their contents. Add an option to print URLs for the sources of the file descriptions. Combine script searches and add a way to map executable names to MIME types (e.g. have a magic value for !:mime which causes the resulting string to be looked up in a table). This would avoid adding the same magic repeatedly for each new hash-bang interpreter. When a file descriptor is available, we can skip and adjust the buffer instead of the hacky buffer management we do now. Fix "name" and "use" to check for consistency at compile time (duplicate "name", "use" pointing to undefined "name" ). Make "name" / "use" more efficient by keeping a sorted list of names. Special-case ^ to flip endianness in the parser so that it does not have to be escaped, and document it. If the offsets specified internally in the file exceed the buffer size ( HOWMANY variable in file.h), then we don't seek to that offset, but we give up. It would be better if buffer managements was done when the file descriptor is available so we can seek around the file. One must be careful though because this has performance and thus security considerations, because one can slow down things by repeateadly seeking. There is support now for keeping separate buffers and having offsets from the end of the file, but the internal buffer management still needs an overhaul.


You can obtain the original author's latest version by anonymous FTP on ftp.astron.com in the directory /pub/file/file-X.YZ.tar.gz. DragonFly 6.1-DEVELOPMENT February 5, 2021 DragonFly 6.1-DEVELOPMENT file(n) Tcl Built-In Commands file(n) ______________________________________________________________________________


file - Manipulate file names and attributes


file option name ?arg arg ...? ______________________________________________________________________________


This command provides several operations on a file's name or attributes. Name is the name of a file; if it starts with a tilde, then tilde substitution is done before executing the command (see the manual entry for filename for details). Option indicates what to do with the file name. Any unique abbreviation for option is acceptable. The valid options are: file atime name ?time? Returns a decimal string giving the time at which file name was last accessed. If time is specified, it is an access time to set for the file. The time is measured in the standard POSIX fashion as seconds from a fixed starting time (often January 1, 1970). If the file does not exist or its access time cannot be queried or set then an error is generated. On Windows, FAT file systems do not support access time. file attributes name file attributes name ?option? file attributes name ?option value option value...? This subcommand returns or sets platform-specific values associated with a file. The first form returns a list of the platform-specific options and their values. The second form returns the value for the given option. The third form sets one or more of the values. The values are as follows: On Unix, -group gets or sets the group name for the file. A group id can be given to the command, but it returns a group name. -owner gets or sets the user name of the owner of the file. The command returns the owner name, but the numerical id can be passed when setting the owner. -permissions retrieves or sets a file's access permissions, using octal notation by default. This option also provides limited support for setting permissions using the symbolic notation accepted by the chmod command, following the form [ugo]?[[+-=][rwxst],[...]]. Multiple permission specifications may be given, separated by commas. E.g., u+s,go-rw would set the setuid bit for a file's owner as well as remove read and write permission for the file's group and other users. An ls-style string of the form rwxrwxrwx is also accepted but must always be 9 characters long. E.g., rwxr- xr-t is equivalent to 01755. On versions of Unix supporting file flags, -readonly returns the value of, or sets, or clears the readonly attribute of a file, i.e., the user immutable flag (uchg) to the chflags command. On Windows, -archive gives the value or sets or clears the archive attribute of the file. -hidden gives the value or sets or clears the hidden attribute of the file. -longname will expand each path element to its long version. This attribute cannot be set. -readonly gives the value or sets or clears the readonly attribute of the file. -shortname gives a string where every path element is replaced with its short (8.3) version of the name. This attribute cannot be set. -system gives or sets or clears the value of the system attribute of the file. On Mac OS X and Darwin, -creator gives or sets the Finder creator type of the file. -hidden gives or sets or clears the hidden attribute of the file. -readonly gives or sets or clears the readonly attribute of the file. -rsrclength gives the length of the resource fork of the file, this attribute can only be set to the value 0, which results in the resource fork being stripped off the file. file channels ?pattern? If pattern is not specified, returns a list of names of all registered open channels in this interpreter. If pattern is specified, only those names matching pattern are returned. Matching is determined using the same rules as for string match. file copy ?-force? ?--? source target file copy ?-force? ?--? source ?source ...? targetDir The first form makes a copy of the file or directory source under the pathname target. If target is an existing directory, then the second form is used. The second form makes a copy inside targetDir of each source file listed. If a directory is specified as a source, then the contents of the directory will be recursively copied into targetDir. Existing files will not be overwritten unless the -force option is specified (when Tcl will also attempt to adjust permissions on the destination file or directory if that is necessary to allow the copy to proceed). When copying within a single filesystem, file copy will copy soft links (i.e. the links themselves are copied, not the things they point to). Trying to overwrite a non-empty directory, overwrite a directory with a file, or overwrite a file with a directory will all result in errors even if -force was specified. Arguments are processed in the order specified, halting at the first error, if any. A -- marks the end of switches; the argument following the -- will be treated as a source even if it starts with a -. file delete ?-force? ?--? ?pathname ... ? Removes the file or directory specified by each pathname argument. Non-empty directories will be removed only if the -force option is specified. When operating on symbolic links, the links themselves will be deleted, not the objects they point to. Trying to delete a non-existent file is not considered an error. Trying to delete a read-only file will cause the file to be deleted, even if the -force flags is not specified. If the -force option is specified on a directory, Tcl will attempt both to change permissions and move the current directory "pwd" out of the given path if that is necessary to allow the deletion to proceed. Arguments are processed in the order specified, halting at the first error, if any. A -- marks the end of switches; the argument following the -- will be treated as a pathname even if it starts with a -. file dirname name Returns a name comprised of all of the path components in name excluding the last element. If name is a relative file name and only contains one path element, then returns ".". If name refers to a root directory, then the root directory is returned. For example, file dirname c:/ returns c:/. Note that tilde substitution will only be performed if it is necessary to complete the command. For example, file dirname ~/src/foo.c returns ~/src, whereas file dirname ~ returns /home (or something similar). file executable name Returns 1 if file name is executable by the current user, 0 otherwise. On Windows, which does not have an executable attribute, the command treats all directories and any files with extensions exe, com, cmd or bat as executable. file exists name Returns 1 if file name exists and the current user has search privileges for the directories leading to it, 0 otherwise. file extension name Returns all of the characters in name after and including the last dot in the last element of name. If there is no dot in the last element of name then returns the empty string. file isdirectory name Returns 1 if file name is a directory, 0 otherwise. file isfile name Returns 1 if file name is a regular file, 0 otherwise. file join name ?name ...? Takes one or more file names and combines them, using the correct path separator for the current platform. If a particular name is relative, then it will be joined to the previous file name argument. Otherwise, any earlier arguments will be discarded, and joining will proceed from the current argument. For example, file join a b /foo bar returns /foo/bar. Note that any of the names can contain separators, and that the result is always canonical for the current platform: / for Unix and Windows. file link ?-linktype? linkName ?target? If only one argument is given, that argument is assumed to be linkName, and this command returns the value of the link given by linkName (i.e. the name of the file it points to). If linkName is not a link or its value cannot be read (as, for example, seems to be the case with hard links, which look just like ordinary files), then an error is returned. If 2 arguments are given, then these are assumed to be linkName and target. If linkName already exists, or if target does not exist, an error will be returned. Otherwise, Tcl creates a new link called linkName which points to the existing filesystem object at target (which is also the returned value), where the type of the link is platform-specific (on Unix a symbolic link will be the default). This is useful for the case where the user wishes to create a link in a cross-platform way, and does not care what type of link is created. If the user wishes to make a link of a specific type only, (and signal an error if for some reason that is not possible), then the optional -linktype argument should be given. Accepted values for -linktype are "-symbolic" and "-hard". On Unix, symbolic links can be made to relative paths, and those paths must be relative to the actual linkName's location (not to the cwd), but on all other platforms where relative links are not supported, target paths will always be converted to absolute, normalized form before the link is created (and therefore relative paths are interpreted as relative to the cwd). Furthermore, "~user" paths are always expanded to absolute form. When creating links on filesystems that either do not support any links, or do not support the specific type requested, an error message will be returned. Most Unix platforms support both symbolic and hard links (the latter for files only). Windows supports symbolic directory links and hard file links on NTFS drives. file lstat name varName Same as stat option (see below) except uses the lstat kernel call instead of stat. This means that if name refers to a symbolic link the information returned in varName is for the link rather than the file it refers to. On systems that do not support symbolic links this option behaves exactly the same as the stat option. file mkdir ?dir ...? Creates each directory specified. For each pathname dir specified, this command will create all non-existing parent directories as well as dir itself. If an existing directory is specified, then no action is taken and no error is returned. Trying to overwrite an existing file with a directory will result in an error. Arguments are processed in the order specified, halting at the first error, if any. file mtime name ?time? Returns a decimal string giving the time at which file name was last modified. If time is specified, it is a modification time to set for the file (equivalent to Unix touch). The time is measured in the standard POSIX fashion as seconds from a fixed starting time (often January 1, 1970). If the file does not exist or its modified time cannot be queried or set then an error is generated. file nativename name Returns the platform-specific name of the file. This is useful if the filename is needed to pass to a platform-specific call, such as to a subprocess via exec under Windows (see EXAMPLES below). file normalize name Returns a unique normalized path representation for the file- system object (file, directory, link, etc), whose string value can be used as a unique identifier for it. A normalized path is an absolute path which has all "../" and "./" removed. Also it is one which is in the "standard" format for the native platform. On Unix, this means the segments leading up to the path must be free of symbolic links/aliases (but the very last path component may be a symbolic link), and on Windows it also means we want the long form with that form's case-dependence (which gives us a unique, case-dependent path). The one exception concerning the last link in the path is necessary, because Tcl or the user may wish to operate on the actual symbolic link itself (for example file delete, file rename, file copy are defined to operate on symbolic links, not on the things that they point to). file owned name Returns 1 if file name is owned by the current user, 0 otherwise. file pathtype name Returns one of absolute, relative, volumerelative. If name refers to a specific file on a specific volume, the path type will be absolute. If name refers to a file relative to the current working directory, then the path type will be relative. If name refers to a file relative to the current working directory on a specified volume, or to a specific file on the current working volume, then the path type is volumerelative. file readable name Returns 1 if file name is readable by the current user, 0 otherwise. file readlink name Returns the value of the symbolic link given by name (i.e. the name of the file it points to). If name is not a symbolic link or its value cannot be read, then an error is returned. On systems that do not support symbolic links this option is undefined. file rename ?-force? ?--? source target file rename ?-force? ?--? source ?source ...? targetDir The first form takes the file or directory specified by pathname source and renames it to target, moving the file if the pathname target specifies a name in a different directory. If target is an existing directory, then the second form is used. The second form moves each source file or directory into the directory targetDir. Existing files will not be overwritten unless the -force option is specified. When operating inside a single filesystem, Tcl will rename symbolic links rather than the things that they point to. Trying to overwrite a non-empty directory, overwrite a directory with a file, or a file with a directory will all result in errors. Arguments are processed in the order specified, halting at the first error, if any. A -- marks the end of switches; the argument following the -- will be treated as a source even if it starts with a -. file rootname name Returns all of the characters in name up to but not including the last "." character in the last component of name. If the last component of name does not contain a dot, then returns name. file separator ?name? If no argument is given, returns the character which is used to separate path segments for native files on this platform. If a path is given, the filesystem responsible for that path is asked to return its separator character. If no file system accepts name, an error is generated. file size name Returns a decimal string giving the size of file name in bytes. If the file does not exist or its size cannot be queried then an error is generated. file split name Returns a list whose elements are the path components in name. The first element of the list will have the same path type as name. All other elements will be relative. Path separators will be discarded unless they are needed to ensure that an element is unambiguously relative. For example, under Unix file split /foo/~bar/baz returns "/ foo ./~bar baz" to ensure that later commands that use the third component do not attempt to perform tilde substitution. file stat name varName Invokes the stat kernel call on name, and uses the variable given by varName to hold information returned from the kernel call. VarName is treated as an array variable, and the following elements of that variable are set: atime, ctime, dev, gid, ino, mode, mtime, nlink, size, type, uid. Each element except type is a decimal string with the value of the corresponding field from the stat return structure; see the manual entry for stat for details on the meanings of the values. The type element gives the type of the file in the same form returned by the command file type. This command returns an empty string. file system name Returns a list of one or two elements, the first of which is the name of the filesystem to use for the file, and the second, if given, an arbitrary string representing the filesystem-specific nature or type of the location within that filesystem. If a filesystem only supports one type of file, the second element may not be supplied. For example the native files have a first element "native", and a second element which when given is a platform-specific type name for the file's system (e.g. "NTFS", "FAT", on Windows). A generic virtual file system might return the list "vfs ftp" to represent a file on a remote ftp site mounted as a virtual filesystem through an extension called "vfs". If the file does not belong to any filesystem, an error is generated. file tail name Returns all of the characters in the last filesystem component of name. Any trailing directory separator in name is ignored. If name contains no separators then returns name. So, file tail a/b, file tail a/b/ and file tail b all return b. file tempfile ?nameVar? ?template? Creates a temporary file and returns a read-write channel opened | on that file. If the nameVar is given, it specifies a variable | that the name of the temporary file will be written into; if | absent, Tcl will attempt to arrange for the temporary file to be | deleted once it is no longer required. If the template is | present, it specifies parts of the template of the filename to | use when creating it (such as the directory, base-name or | extension) though some platforms may ignore some or all of these | parts and use a built-in default instead. | Note that temporary files are only ever created on the native | filesystem. As such, they can be relied upon to be used with | operating-system native APIs and external programs that require | a filename. | file type name Returns a string giving the type of file name, which will be one of file, directory, characterSpecial, blockSpecial, fifo, link, or socket. file volumes Returns the absolute paths to the volumes mounted on the system, as a proper Tcl list. Without any virtual filesystems mounted as root volumes, on UNIX, the command will always return "/", since all filesystems are locally mounted. On Windows, it will return a list of the available local drives (e.g. "a:/ c:/"). If any virtual filesystem has mounted additional volumes, they will be in the returned list. file writable name Returns 1 if file name is writable by the current user, 0 otherwise.


Unix These commands always operate using the real user and group identifiers, not the effective ones. Windows The file owned subcommand uses the user identifier (SID) of the process token, not the thread token which may be impersonating some other user.


This procedure shows how to search for C files in a given directory that have a correspondingly-named object file in the current directory: proc findMatchingCFiles {dir} { set files {} switch $::tcl_platform(platform) { windows { set ext .obj } unix { set ext .o } } foreach file [glob -nocomplain -directory $dir *.c] { set objectFile [file tail [file rootname $file]]$ext if {[file exists $objectFile]} { lappend files $file } } return $files } Rename a file and leave a symbolic link pointing from the old location to the new place: set oldName foobar.txt set newName foo/bar.txt # Make sure that where we're going to move to exists... if {![file isdirectory [file dirname $newName]]} { file mkdir [file dirname $newName] } file rename $oldName $newName file link -symbolic $oldName $newName On Windows, a file can be "started" easily enough (equivalent to double-clicking on it in the Explorer interface) but the name passed to the operating system must be in native format: exec {*}[auto_execok start] {} [file nativename ~/example.txt]


filename(n), open(n), close(n), eof(n), gets(n), tell(n), seek(n), fblocked(n), flush(n)


attributes, copy files, delete files, directory, file, move files, name, rename files, stat, user Tcl 8.3 file(n)

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