Changes the file protection of a file.

    Format

      #include  <stat.h>

      int chmod  (const char *file_spec, mode_t mode);

1 - Arguments

 file_spec

    The name of an OpenVMS or UNIX style file specification.

 mode

    A file protection. Modes are constructed by performing a bitwise
    OR on any of the values shown in File Protection Values and Their
    Meanings.

    Table REF-2 File Protection Values and Their Meanings

    Value  Privilege

    0400   OWNER:READ
    0200   OWNER:WRITE
    0100   OWNER:EXECUTE
    0040   GROUP:READ
    0020   GROUP:WRITE
    0010   GROUP:EXECUTE
    0004   WORLD:READ
    0002   WORLD:WRITE
    0001   WORLD:EXECUTE

    When you supply a mode value of 0, the chmod function gives the
    file the user's default file protection.

    The system is given the same privileges as the owner. A WRITE
    privilege also implies a DELETE privilege.

2 - Description

    You must have a WRITE privilege for the file specified to change
    the mode.

    The C RTL does not support the S_ISVTX bit. Setting the S_ISVTX
    mode has no effect.

3 - Return Values

    0                  Indicates that the mode is successfully
                       changed.
    -1                 Indicates that the change attempt has failed.