focal (2) getresgid.2freebsd.gz

NAME

     getresgid, getresuid, setresgid, setresuid — get or set real, effective and saved user or group ID

LIBRARY

     Standard C Library (libc, -lc)

SYNOPSIS

     #include <sys/types.h>
     #include <unistd.h>

     int
     getresgid(gid_t *rgid, gid_t *egid, gid_t *sgid);

     int
     getresuid(uid_t *ruid, uid_t *euid, uid_t *suid);

     int
     setresgid(gid_t rgid, gid_t egid, gid_t sgid);

     int
     setresuid(uid_t ruid, uid_t euid, uid_t suid);

DESCRIPTION

     The setresuid() system call sets the real, effective and saved user IDs of the current process.  The
     analogous setresgid() sets the real, effective and saved group IDs.

     Privileged processes may set these IDs to arbitrary values.  Unprivileged processes are restricted in that
     each of the new IDs must match one of the current IDs.

     Passing -1 as an argument causes the corresponding value to remain unchanged.

     The getresgid() and getresuid() calls retrieve the real, effective, and saved group and user IDs of the
     current process, respectively.

RETURN VALUES

     Upon successful completion, the value 0 is returned; otherwise the value -1 is returned and the global
     variable errno is set to indicate the error.

ERRORS

     [EPERM]            The calling process was not privileged and tried to change one or more IDs to a value
                        which was not the current real ID, the current effective ID nor the current saved ID.

     [EFAULT]           An address passed to getresgid() or getresuid() was invalid.

SEE ALSO

     getegid(2), geteuid(2), getgid(2), getuid(2), issetugid(2), setgid(2), setregid(2), setreuid(2), setuid(2)

HISTORY

     These functions first appeared in HP-UX.