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file(n)




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NAME

       file - Manipulate file names and attributes


SYNOPSIS

       file option name ?arg arg ...?
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DESCRIPTION

       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 doesn't 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 associ-
              ated  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:

              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  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:  u+s,go-rw  add  sticky  bit for user, remove read and
              write permissions for group and other).  A simplified  ls  style
              string,  of  the  form rwxrwxrwx (must be 9 characters), is also
              supported (example: rwxr-xr-t is equivalent to 01755).

              On Windows, -archive gives the value or sets or clears  the  ar-
              chive  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 Macintosh, -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. Note that directories can only be locked
              if File Sharing is turned on. -type gives  or  sets  the  Finder
              file type for the file.

       file channels ?pat-                                                     |
       tern?                                                 |                 |
              If pattern isn't specified, returns a list of names of all  reg- |
              istered open channels in this interpreter.  If pattern is speci- |
              fied, 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 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 ?pathname ... ?
              Removes  the  file or directory specified by each pathname argu-
              ment.  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, halt-
              ing 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 ``.'' (or ``:''  on
              the  Macintosh).   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 oth-
              erwise.

       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 cor-
              rect 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  dis-
              carded, 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, and : for Macintosh.

       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 isn't a link or its value cannot be read (as, for exam-
              ple, 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 doesn't exist, an error
              will be returned.  Otherwise, Tcl  creates  a  new  link  called
              linkName  which points to the existing filesystem object at tar-
              get, 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  doesn't  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".  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 sym-
              bolic and hard links (the latter for files only), MacOS supports
              symbolic  links  and Windows NT/2000/XP (on NTFS drives) support
              symbolic directory links and hard file links.

       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 sym-
              bolic link the information returned in varName is for  the  link
              rather  than  the file it refers to.  On systems that don't sup-
              port symbolic links this option behaves exactly the same as  the
              stat option.

       file mkdir dir ?dir ...?
              Creates  each directory specified.  For each pathname dir speci-
              fied, this command will create all non-existing parent  directo-
              ries  as well as dir itself.  If an existing directory is speci-
              fied, 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 doesn't
              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 exec under Windows or AppleScript on the Macintosh.

       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 '../', './' removed.  Also it  is
              one which is in the ``standard'' format for the native platform.
              On MacOS, 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 con-
              cerning  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 other-
              wise.

       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 cur-
              rent 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 file type is volumerelative.

       file readable name
              Returns 1 if file name is readable by the current user, 0 other-
              wise.

       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 isn't a  symbolic  link
              or its value cannot be read, then an error is returned.  On sys-
              tems that don't 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 tar-
              getDir. 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 speci-
              fied, 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 doesn't 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 doesn't 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 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  substi-
              tution.

       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 follow-
              ing 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  ele-
              ment 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 two elements, the first of which is  the  name
              of  the  filesystem to use for the file, and the second an arbi-
              trary 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 be null.   For
              example  the  native  files have a first element 'native', and a
              second element which is a platform-specific type  name  for  the
              file's  system  (e.g. 'NTFS', 'FAT', etc), or possibly the empty
              string if no further information is available or if this is  not
              implemented.   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  gener-
              ated.

       file tail name
              Returns  all  of the characters in name after the last directory
              separator.  If name contains no separators then returns name.

       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.  On the Macintosh, this will be a list of
              the mounted drives, both local and network.  N.B. if two  drives
              have  the  same  name, they will both appear on the volume list,
              but there is currently no way, from Tcl, to access any  but  the
              first  of these drives.  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:/}).

       file writable name
              Returns 1 if file name is writable by the current user, 0 other-
              wise.


PORTABILITY ISSUES

       Unix
              These  commands  always  operate  using  the real user and group
              identifiers, not the effective ones.


EXAMPLES

       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


SEE ALSO

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


KEYWORDS

       attributes, copy files, delete  files,  directory,  file,  move  files,
       name, rename files, stat

Tcl                                   8.3                              file(n)

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