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diff --git a/doc/file.n b/doc/file.n new file mode 100644 index 0000000..5ff45fd --- /dev/null +++ b/doc/file.n @@ -0,0 +1,550 @@ +'\" +'\" Copyright (c) 1993 The Regents of the University of California. +'\" Copyright (c) 1994-1996 Sun Microsystems, Inc. +'\" +'\" See the file "license.terms" for information on usage and redistribution +'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES. +'\" +.TH file n 8.3 Tcl "Tcl Built-In Commands" +.so man.macros +.BS +'\" Note: do not modify the .SH NAME line immediately below! +.SH NAME +file \- Manipulate file names and attributes +.SH SYNOPSIS +\fBfile \fIoption\fR \fIname\fR ?\fIarg arg ...\fR? +.BE +.SH DESCRIPTION +.PP +This command provides several operations on a file's name or attributes. +\fIName\fR 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 +\fBfilename\fR for details). \fIOption\fR indicates what to do with the +file name. Any unique abbreviation for \fIoption\fR is acceptable. The +valid options are: +.TP +\fBfile atime \fIname\fR ?\fBtime\fR? +. +Returns a decimal string giving the time at which file \fIname\fR was last +accessed. If \fItime\fR 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. +.TP +\fBfile attributes \fIname\fR +.TP +\fBfile attributes \fIname\fR ?\fBoption\fR? +.TP +\fBfile attributes \fIname\fR ?\fBoption value option value...\fR? +. +This subcommand returns or sets platform specific values associated +with a file. The first form returns a list of the platform specific +flags and their values. The second form returns the value for the +specific option. The third form sets one or more of the values. The +values are as follows: +.RS +.PP +On Unix, \fB\-group\fR gets or sets the group name for the file. A group id +can be given to the command, but it returns a group name. \fB\-owner\fR 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. \fB\-permissions\fR sets or retrieves the octal code that chmod(1) +uses. This command does also has limited support for setting using the +symbolic attributes for chmod(1), of the form [ugo]?[[+\-=][rwxst],[...]], +where multiple symbolic attributes can be separated by commas (example: +\fBu+s,go\-rw\fR add sticky bit for user, remove read and write +permissions for group and other). A simplified \fBls\fR style string, +of the form rwxrwxrwx (must be 9 characters), is also supported +(example: \fBrwxr\-xr\-t\fR is equivalent to 01755). +On versions of Unix supporting file flags, \fB\-readonly\fR gives the +value or sets or clears the readonly attribute of the file, +i.e. the user immutable flag \fBuchg\fR to chflags(1). +.PP +On Windows, \fB\-archive\fR gives the value or sets or clears the +archive attribute of the file. \fB\-hidden\fR gives the value or sets +or clears the hidden attribute of the file. \fB\-longname\fR will +expand each path element to its long version. This attribute cannot be +set. \fB\-readonly\fR gives the value or sets or clears the readonly +attribute of the file. \fB\-shortname\fR gives a string where every +path element is replaced with its short (8.3) version of the +name. This attribute cannot be set. \fB\-system\fR gives or sets or +clears the value of the system attribute of the file. +.PP +On Mac OS X and Darwin, \fB\-creator\fR gives or sets the +Finder creator type of the file. \fB\-hidden\fR gives or sets or clears +the hidden attribute of the file. \fB\-readonly\fR gives or sets or +clears the readonly attribute of the file. \fB\-rsrclength\fR 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. +.RE +.TP +\fBfile channels ?\fIpattern\fR? +. +If \fIpattern\fR is not specified, returns a list of names of all +registered open channels in this interpreter. If \fIpattern\fR is +specified, only those names matching \fIpattern\fR are returned. Matching +is determined using the same rules as for \fBstring match\fR. +.TP +\fBfile copy \fR?\fB\-force\fR? ?\fB\-\|\-\fR? \fIsource\fR \fItarget\fR +.TP +\fBfile copy \fR?\fB\-force\fR? ?\fB\-\|\-\fR? \fIsource\fR ?\fIsource\fR ...? \fItargetDir\fR +. +The first form makes a copy of the file or directory \fIsource\fR under +the pathname \fItarget\fR. If \fItarget\fR is an existing directory, +then the second form is used. The second form makes a copy inside +\fItargetDir\fR of each \fIsource\fR file listed. If a directory is +specified as a \fIsource\fR, then the contents of the directory will be +recursively copied into \fItargetDir\fR. Existing files will not be +overwritten unless the \fB\-force\fR 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, \fIfile copy\fR 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 +\fB\-force\fR was specified. Arguments are processed in the order +specified, halting at the first error, if any. A \fB\-\|\-\fR marks +the end of switches; the argument following the \fB\-\|\-\fR will be +treated as a \fIsource\fR even if it starts with a \fB\-\fR. +.TP +\fBfile delete \fR?\fB\-force\fR? ?\fB\-\|\-\fR? ?\fIpathname\fR ... ? +. +Removes the file or directory specified by each \fIpathname\fR +argument. Non-empty directories will be removed only if the +\fB\-force\fR 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 \fB\-force\fR flags is not specified. If the \fB\-force\fR +option is specified on a directory, Tcl will attempt both to change +permissions and move the current directory +.QW 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 \fB\-\|\-\fR marks the end of switches; the argument following the +\fB\-\|\-\fR will be treated as a \fIpathname\fR even if it starts with +a \fB\-\fR. +.TP +\fBfile dirname \fIname\fR +Returns a name comprised of all of the path components in \fIname\fR +excluding the last element. If \fIname\fR is a relative file name and +only contains one path element, then returns +.QW \fB.\fR . +If \fIname\fR refers to a root directory, then the root directory is +returned. For example, +.RS +.PP +.CS +\fBfile dirname\fR c:/ +.CE +.PP +returns \fBc:/\fR. +.PP +Note that tilde substitution will only be +performed if it is necessary to complete the command. For example, +.PP +.CS +\fBfile dirname\fR ~/src/foo.c +.CE +.PP +returns \fB~/src\fR, whereas +.PP +.CS +\fBfile dirname\fR ~ +.CE +.PP +returns \fB/home\fR (or something similar). +.RE +.TP +\fBfile executable \fIname\fR +. +Returns \fB1\fR if file \fIname\fR is executable by the current user, +\fB0\fR otherwise. +.TP +\fBfile exists \fIname\fR +. +Returns \fB1\fR if file \fIname\fR exists and the current user has +search privileges for the directories leading to it, \fB0\fR otherwise. +.TP +\fBfile extension \fIname\fR +. +Returns all of the characters in \fIname\fR after and including the last +dot in the last element of \fIname\fR. If there is no dot in the last +element of \fIname\fR then returns the empty string. +.TP +\fBfile isdirectory \fIname\fR +. +Returns \fB1\fR if file \fIname\fR is a directory, \fB0\fR otherwise. +.TP +\fBfile isfile \fIname\fR +. +Returns \fB1\fR if file \fIname\fR is a regular file, \fB0\fR otherwise. +.TP +\fBfile join \fIname\fR ?\fIname ...\fR? +. +Takes one or more file names and combines them, using the correct path +separator for the current platform. If a particular \fIname\fR 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, +.RS +.PP +.CS +\fBfile join\fR a b /foo bar +.CE +.PP +returns \fB/foo/bar\fR. +.PP +Note that any of the names can contain separators, and that the result +is always canonical for the current platform: \fB/\fR for Unix and +Windows. +.RE +.TP +\fBfile link ?\fI\-linktype\fR? \fIlinkName\fR ?\fItarget\fR? +. +If only one argument is given, that argument is assumed to be +\fIlinkName\fR, and this command returns the value of the link given by +\fIlinkName\fR (i.e. the name of the file it points to). If +\fIlinkName\fR 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. +.RS +.PP +If 2 arguments are given, then these are assumed to be \fIlinkName\fR +and \fItarget\fR. If \fIlinkName\fR already exists, or if \fItarget\fR +does not exist, an error will be returned. Otherwise, Tcl creates a new +link called \fIlinkName\fR which points to the existing filesystem +object at \fItarget\fR (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. +.PP +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 +\fI\-linktype\fR argument should be given. Accepted values for +\fI\-linktype\fR are +.QW \fB\-symbolic\fR +and +.QW \fB\-hard\fR . +.PP +On Unix, symbolic links can be made to relative paths, and those paths +must be relative to the actual \fIlinkName\fR'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, +.QW ~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. In particular Windows 95, 98 and ME do +not support any links at present, but most Unix platforms support both +symbolic and hard links (the latter for files only) and Windows +NT/2000/XP (on NTFS drives) support symbolic +directory links and hard file links. +.RE +.TP +\fBfile lstat \fIname varName\fR +. +Same as \fBstat\fR option (see below) except uses the \fIlstat\fR +kernel call instead of \fIstat\fR. This means that if \fIname\fR +refers to a symbolic link the information returned in \fIvarName\fR +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 \fBstat\fR option. +.TP +\fBfile mkdir ?\fIdir\fR ...? +. +Creates each directory specified. For each pathname \fIdir\fR specified, +this command will create all non-existing parent directories as +well as \fIdir\fR 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. +.TP +\fBfile mtime \fIname\fR ?\fItime\fR? +. +Returns a decimal string giving the time at which file \fIname\fR was last +modified. If \fItime\fR is specified, it is a modification time to set for +the file (equivalent to Unix \fBtouch\fR). 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. +.TP +\fBfile nativename \fIname\fR +. +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 \fBexec\fR under Windows (see \fBEXAMPLES\fR below). +.TP +\fBfile normalize \fIname\fR +. +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 +.QW ../ +and +.QW ./ +removed. Also it is one which is in the +.QW 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 \fBfile delete\fR, +\fBfile rename\fR, \fBfile copy\fR are defined to operate on symbolic +links, not on the things that they point to). +.TP +\fBfile owned \fIname\fR +. +Returns \fB1\fR if file \fIname\fR is owned by the current user, \fB0\fR +otherwise. +.TP +\fBfile pathtype \fIname\fR +. +Returns one of \fBabsolute\fR, \fBrelative\fR, \fBvolumerelative\fR. If +\fIname\fR refers to a specific file on a specific volume, the path type will +be \fBabsolute\fR. If \fIname\fR refers to a file relative to the current +working directory, then the path type will be \fBrelative\fR. If \fIname\fR +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 \fBvolumerelative\fR. +.TP +\fBfile readable \fIname\fR +. +Returns \fB1\fR if file \fIname\fR is readable by the current user, +\fB0\fR otherwise. +.TP +\fBfile readlink \fIname\fR +. +Returns the value of the symbolic link given by \fIname\fR (i.e. the name +of the file it points to). If \fIname\fR 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. +.TP +\fBfile rename \fR?\fB\-force\fR? ?\fB\-\|\-\fR? \fIsource\fR \fItarget\fR +.TP +\fBfile rename \fR?\fB\-force\fR? ?\fB\-\|\-\fR? \fIsource\fR ?\fIsource\fR ...? \fItargetDir\fR +. +The first form takes the file or directory specified by pathname +\fIsource\fR and renames it to \fItarget\fR, moving the file if the +pathname \fItarget\fR specifies a name in a different directory. If +\fItarget\fR is an existing directory, then the second form is used. +The second form moves each \fIsource\fR file or directory into the +directory \fItargetDir\fR. Existing files will not be overwritten +unless the \fB\-force\fR 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 \fB\-\|\-\fR marks the end of +switches; the argument following the \fB\-\|\-\fR will be treated as a +\fIsource\fR even if it starts with a \fB\-\fR. +.TP +\fBfile rootname \fIname\fR +. +Returns all of the characters in \fIname\fR up to but not including the +last +.QW . +character in the last component of name. If the last +component of \fIname\fR does not contain a dot, then returns \fIname\fR. +.TP +\fBfile separator\fR ?\fIname\fR? +. +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 \fIname\fR, an error +is generated. +.TP +\fBfile size \fIname\fR +. +Returns a decimal string giving the size of file \fIname\fR in bytes. If +the file does not exist or its size cannot be queried then an error is +generated. +.TP +\fBfile split \fIname\fR +. +Returns a list whose elements are the path components in \fIname\fR. The +first element of the list will have the same path type as \fIname\fR. +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 +.RS +.PP +.CS +\fBfile split\fR /foo/~bar/baz +.CE +.PP +returns +.QW \fB/\0\0foo\0\0./~bar\0\0baz\fR +to ensure that later commands +that use the third component do not attempt to perform tilde +substitution. +.RE +.TP +\fBfile stat \fIname varName\fR +. +Invokes the \fBstat\fR kernel call on \fIname\fR, and uses the variable +given by \fIvarName\fR to hold information returned from the kernel call. +\fIVarName\fR is treated as an array variable, and the following elements +of that variable are set: \fBatime\fR, \fBctime\fR, \fBdev\fR, \fBgid\fR, +\fBino\fR, \fBmode\fR, \fBmtime\fR, \fBnlink\fR, \fBsize\fR, \fBtype\fR, +\fBuid\fR. Each element except \fBtype\fR is a decimal string with the +value of the corresponding field from the \fBstat\fR return structure; +see the manual entry for \fBstat\fR for details on the meanings of the +values. The \fBtype\fR element gives the type of the file in the same +form returned by the command \fBfile type\fR. This command returns an +empty string. +.TP +\fBfile system \fIname\fR +. +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 +.QW native , +and a second element which when given is a platform-specific type name +for the file's system (e.g. +.QW NTFS , +.QW FAT , +on Windows). A generic virtual file system might return +the list +.QW "vfs ftp" +to represent a file on a remote ftp site mounted as a +virtual filesystem through an extension called +.QW vfs . +If the file does not belong to any filesystem, an error is generated. +.TP +\fBfile tail \fIname\fR +. +Returns all of the characters in the last filesystem component of +\fIname\fR. Any trailing directory separator in \fIname\fR is ignored. +If \fIname\fR contains no separators then returns \fIname\fR. So, +\fBfile tail a/b\fR, \fBfile tail a/b/\fR and \fBfile tail b\fR all +return \fBb\fR. +.TP +\fBfile tempfile\fR ?\fInameVar\fR? ?\fItemplate\fR? +'\" TIP #210 +.VS 8.6 +Creates a temporary file and returns a read-write channel opened on that file. +If the \fInameVar\fR 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 +\fItemplate\fR 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. +.RS +.PP +Note that temporary files are \fIonly\fR 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. +.RE +.VE 8.6 +.TP +\fBfile type \fIname\fR +. +Returns a string giving the type of file \fIname\fR, which will be one of +\fBfile\fR, \fBdirectory\fR, \fBcharacterSpecial\fR, \fBblockSpecial\fR, +\fBfifo\fR, \fBlink\fR, or \fBsocket\fR. +.TP +\fBfile volumes\fR +. +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 +.QW / , +since all filesystems are locally mounted. +On Windows, it will return a list of the available local drives +(e.g. +.QW "a:/ c:/" ). +If any virtual filesystem has mounted additional +volumes, they will be in the returned list. +.TP +\fBfile writable \fIname\fR +. +Returns \fB1\fR if file \fIname\fR is writable by the current user, +\fB0\fR otherwise. +.SH "PORTABILITY ISSUES" +.TP +\fBUnix\fR\0\0\0\0\0\0\0 +. +These commands always operate using the real user and group identifiers, +not the effective ones. +.TP +\fBWindows\fR\0\0\0\0 +. +The \fBfile owned\fR subcommand currently always reports that the current user +is the owner of the file, without regard for what the operating system +believes to be true, making an ownership test useless. This issue (#3613671) +may be fixed in a future release of Tcl. +.SH EXAMPLES +.PP +This procedure shows how to search for C files in a given directory +that have a correspondingly-named object file in the current +directory: +.PP +.CS +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 [\fBfile tail\fR [\fBfile rootname\fR $file]]$ext + if {[\fBfile exists\fR $objectFile]} { + lappend files $file + } + } + return $files +} +.CE +.PP +Rename a file and leave a symbolic link pointing from the old location +to the new place: +.PP +.CS +set oldName foobar.txt +set newName foo/bar.txt +# Make sure that where we're going to move to exists... +if {![\fBfile isdirectory\fR [\fBfile dirname\fR $newName]]} { + \fBfile mkdir\fR [\fBfile dirname\fR $newName] +} +\fBfile rename\fR $oldName $newName +\fBfile link\fR \-symbolic $oldName $newName +.CE +.PP +On Windows, a file can be +.QW 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: +.PP +.CS +exec {*}[auto_execok start] {} [\fBfile nativename\fR ~/example.txt] +.CE +.SH "SEE ALSO" +filename(n), open(n), close(n), eof(n), gets(n), tell(n), seek(n), +fblocked(n), flush(n) +.SH KEYWORDS +attributes, copy files, delete files, directory, file, move files, name, +rename files, stat, user +'\" Local Variables: +'\" mode: nroff +'\" fill-column: 78 +'\" End: |