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Diffstat (limited to 'doc/filename.n')
| -rw-r--r-- | doc/filename.n | 148 |
1 files changed, 52 insertions, 96 deletions
diff --git a/doc/filename.n b/doc/filename.n index b588440..1fe22f0 100644 --- a/doc/filename.n +++ b/doc/filename.n @@ -23,7 +23,6 @@ to be portable should not assume a particular form for file names. Instead, portable scripts must use the \fBfile split\fR and \fBfile join\fR commands to manipulate file names (see the \fBfile\fR manual entry for more details). - .SH "PATH TYPES" .PP File names are grouped into three general types based on the starting point @@ -36,76 +35,26 @@ qualified, either giving the path relative to the root directory on the current volume, or relative to the current directory of the specified volume. The \fBfile pathtype\fR command can be used to determine the type of a given path. - .SH "PATH SYNTAX" .PP The rules for native names depend on the value reported in the Tcl array element \fBtcl_platform(platform)\fR: .TP 10 -\fBmac\fR -On Apple Macintosh systems, Tcl supports two forms of path names. The -normal Mac style names use colons as path separators. Paths may be -relative or absolute, and file names may contain any character other -than colon. A leading colon causes the rest of the path to be -interpreted relative to the current directory. If a path contains a -colon that is not at the beginning, then the path is interpreted as an -absolute path. Sequences of two or more colons anywhere in the path -are used to construct relative paths where \fB::\fR refers to the -parent of the current directory, \fB:::\fR refers to the parent of the -parent, and so forth. +\fBUnix\fR +On Unix and Apple MacOS X platforms, Tcl uses path names where the +components are separated by slashes. Path names may be relative or +absolute, and file names may contain any character other than slash. +The file names \fB\&.\fR and \fB\&..\fR are special and refer to the +current directory and the parent of the current directory respectively. +Multiple adjacent slash characters are interpreted as a single +separator. Any number of trailing slash characters at the end of a +path are simply ignored, so the paths \fBfoo\fR, \fBfoo/\fR and +\fBfoo//\fR are all identical, and in particular \fBfoo/\fR does not +necessarily mean a directory is being referred. .RS .PP -In addition to Macintosh style names, Tcl also supports a subset of -Unix-like names. If a path contains no colons, then it is interpreted -like a Unix path. Slash is used as the path separator. The file name -\fB\&.\fR refers to the current directory, and \fB\&..\fR refers to the -parent of the current directory. However, some names like \fB/\fR or -\fB/..\fR have no mapping, and are interpreted as Macintosh names. In -general, commands that generate file names will return Macintosh style -names, but commands that accept file names will take both Macintosh -and Unix-style names. -.PP -The following examples illustrate various forms of path names: -.TP 15 -\fB:\fR -Relative path to the current folder. -.TP 15 -\fBMyFile\fR -Relative path to a file named \fBMyFile\fR in the current folder. -.TP 15 -\fBMyDisk:MyFile\fR -Absolute path to a file named \fBMyFile\fR on the device named \fBMyDisk\fR. -.TP 15 -\fB:MyDir:MyFile\fR -Relative path to a file name \fBMyFile\fR in a folder named -\fBMyDir\fR in the current folder. -.TP 15 -\fB::MyFile\fR -Relative path to a file named \fBMyFile\fR in the folder above the -current folder. -.TP 15 -\fB:::MyFile\fR -Relative path to a file named \fBMyFile\fR in the folder two levels above the -current folder. -.TP 15 -\fB/MyDisk/MyFile\fR -Absolute path to a file named \fBMyFile\fR on the device named -\fBMyDisk\fR. -.TP 15 -\fB\&../MyFile\fR -Relative path to a file named \fBMyFile\fR in the folder above the -current folder. -.RE -.TP -\fBunix\fR -On Unix platforms, Tcl uses path names where the components are -separated by slashes. Path names may be relative or absolute, and -file names may contain any character other than slash. The file names -\fB\&.\fR and \fB\&..\fR are special and refer to the current directory -and the parent of the current directory respectively. Multiple -adjacent slash characters are interpreted as a single separator. -The following examples illustrate various forms of path names: -.RS +The following examples illustrate various forms of path +names: .TP 15 \fB/\fR Absolute path to the root directory. @@ -129,7 +78,7 @@ Relative path to the file \fBfoo\fR in the directory above the current directory. .RE .TP -\fBwindows\fR +\fBWindows\fR On Microsoft Windows platforms, Tcl supports both drive-relative and UNC style names. Both \fB/\fR and \fB\e\fR may be used as directory separators in either type of name. Drive-relative names consist of an optional drive @@ -169,37 +118,39 @@ Volume-relative path to a file \fBfoo\fR in the root directory of the current volume. This is not a valid UNC path, so the assumption is that the extra backslashes are superfluous. .RE - .SH "TILDE SUBSTITUTION" .PP In addition to the file name rules described above, Tcl also supports -\fIcsh\fR-style tilde substitution. If a file name starts with a -tilde, then the file name will be interpreted as if the first element -is replaced with the location of the home directory for the given -user. If the tilde is followed immediately by a separator, then the -\fB$HOME\fR environment variable is substituted. Otherwise the -characters between the tilde and the next separator are taken as a -user name, which is used to retrieve the user's home directory for -substitution. +\fIcsh\fR-style tilde substitution. If a file name starts with a tilde, +then the file name will be interpreted as if the first element is +replaced with the location of the home directory for the given user. If +the tilde is followed immediately by a separator, then the \fB$HOME\fR +environment variable is substituted. Otherwise the characters between +the tilde and the next separator are taken as a user name, which is used +to retrieve the user's home directory for substitution. This works on +Unix, MacOS X and Windows (except very old releases). .PP -The Macintosh and Windows platforms do not support tilde substitution -when a user name follows the tilde. On these platforms, attempts to -use a tilde followed by a user name will generate an error that the -user does not exist when Tcl attempts to interpret that part of the -path or otherwise access the file. The behaviour of these paths -when not trying to interpret them is the same as on Unix. File -names that have a tilde without a user name will be correctly -substituted using the \fB$HOME\fR environment variable, just like -for Unix. - +Old Windows platforms do not support tilde substitution when a user name +follows the tilde. On these platforms, attempts to use a tilde followed +by a user name will generate an error that the user does not exist when +Tcl attempts to interpret that part of the path or otherwise access the +file. The behaviour of these paths when not trying to interpret them is +the same as on Unix. File names that have a tilde without a user name +will be correctly substituted using the \fB$HOME\fR environment +variable, just like for Unix. .SH "PORTABILITY ISSUES" .PP Not all file systems are case sensitive, so scripts should avoid code that depends on the case of characters in a file name. In addition, the character sets allowed on different devices may differ, so scripts should choose file names that do not contain special characters like: -\fB<>:"/\e|\fR. The safest approach is to use names consisting of -alphanumeric characters only. Also Windows 3.1 only supports file +\fB<>:?"/\e|\fR. +'\""\" reset emacs highlighting +The safest approach is to use names consisting of +alphanumeric characters only. Care should be taken with filenames +which contain spaces (common on Windows systems) and +filenames where the backslash is the directory separator (Windows +native path names). Also Windows 3.1 only supports file names with a root of no more than 8 characters and an extension of no more than 3 characters. .PP @@ -207,16 +158,21 @@ On Windows platforms there are file and path length restrictions. Complete paths or filenames longer than about 260 characters will lead to errors in most file operations. .PP -Another Windows peculiarity is that any number of trailing dots '.' in -filenames are totally ignored, so, for example, attempts to create a -file or directory with a name "foo." will result in the creation of a -file/directory with name "foo". This fact is reflected in the -results of 'file normalize'. Furthermore, a file name consisting only -of dots '.........' or dots with trailing characters '.....abc' is -illegal. +Another Windows peculiarity is that any number of trailing dots +.QW . +in filenames are totally ignored, so, for example, attempts to create a +file or directory with a name +.QW foo. +will result in the creation of a file/directory with name +.QW foo . +This fact is reflected in the results of \fBfile normalize\fR. +Furthermore, a file name consisting only of dots +.QW ......... +or dots with trailing characters +.QW .....abc +is illegal. +.SH "SEE ALSO" +file(n), glob(n) .SH KEYWORDS current directory, absolute file name, relative file name, volume-relative file name, portability - -.SH "SEE ALSO" -file(n), glob(n) |