SETUID(2-POSIX)     RISC/os Reference Manual      SETUID(2-POSIX)



NAME
     setuid, setgid - set user and group IDs

SYNOPSIS
     #include <sys/types.h>

     int setuid (uid)
     uidt uid;

     int setgid (gid)
     gidt gid;

DESCRIPTION
     setuid (setgid) is used to set the real user (group) ID and
     effective user (group) ID of the calling process.

     If the effective user ID of the calling process is super-
     user, the real user (group) ID, effective user (group) ID,
     and saved set-user (group) ID are set to uid (gid).

     If the effective user ID of the calling process is not
     super-user, but its real user (group) ID is equal to uid
     (gid), the effective user (group) ID is set to uid (gid).

     If the effective user ID of the calling process is not
     super-user, but the saved set-user (group) ID from exec(2)
     is equal to uid (gid), the effective user (group) ID is set
     to uid (gid).

     setuid (setgid) will fail if the real user (group) ID of the
     calling process is not equal to uid (gid) and its effective
     user ID is not super-user.

RETURN VALUES
     Upon successful completion, a value of 0 is returned.  Oth-
     erwise, a value of -1 is returned and errno is set to indi-
     cate the error.

ERRORS
     If the following condition occurs, setuid and setgid return
     -1 and set errno to the corresponding value:

     [EPERM]             The effective user ID is not the
                         superuser, and uid (gid) does not match
                         the read uid (gid) or the saved set-user
                         (group) ID.

SEE ALSO
     getuid(2), intro(2).






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