NAME

       Tcl_Access, Tcl_Stat - check file permissions and other attributes

SYNOPSIS

       #include <tcl.h>

       int
       Tcl_Access(path, mode)

       int
       Tcl_Stat(path, statPtr)

ARGUMENTS

       char *path (in)                    Native name of the file to check the attributes of.

       int mode (in)                      Mask  consisting of one or more of R_OK, W_OK, X_OK and
                                          F_OK.  R_OK, W_OK and X_OK request checking whether the
                                          file   exists   and   has   read,  write  and   execute
                                          permissions, respectively.  F_OK just requests checking
                                          for the existence of the file.

       struct stat *statPtr (out)         The structure that contains the result.
_________________________________________________________________________________________________

DESCRIPTION

       As  of  Tcl  8.4,  the  object-based  APIs  Tcl_FSAccess  and Tcl_FSStat should be used in
       preference to Tcl_Access and Tcl_Stat, wherever possible.

       There are two reasons for calling Tcl_Access and Tcl_Stat rather than calling system level
       functions  access  and stat directly.  First, the Windows implementation of both functions
       fixes some bugs in the system level calls.  Second, both Tcl_Access and Tcl_Stat (as  well
       as  Tcl_OpenFileChannelProc)  hook  into  a  linked  list  of  functions.  This allows the
       possibility to reroute file access to alternative media or access methods.

       Tcl_Access checks whether the process  would  be  allowed  to  read,  write  or  test  for
       existence  of the file (or other file system object) whose name is pathname.   If pathname
       is a symbolic link on Unix, then permissions of the file referred by  this  symbolic  link
       are tested.

       On  success (all requested permissions granted), zero is returned.  On error (at least one
       bit in mode asked for a permission that is denied, or some other  error occurred),  -1  is
       returned.

       Tcl_Stat  fills the stat structure statPtr with information about the specified file.  You
       do not need any access rights to the file to get this  information  but  you  need  search
       rights  to  all  directories  named  in  the path leading to the file.  The stat structure
       includes info regarding device, inode (always 0 on Windows), privilege mode, nlink (always
       1  on  Windows), user id (always 0 on Windows), group id (always 0 on Windows), rdev (same
       as device on Windows), size, last access time, last modification time, and creation time.

       If path exists, Tcl_Stat returns 0 and the stat structure is filled with data.  Otherwise,
       -1 is returned, and no stat info is given.

KEYWORDS

       stat, access