hpux man page for setresgid

setresuid(2)							System Calls Manual						      setresuid(2)

NAME
       setresuid, setresgid - set real, effective, and saved user and group IDs

SYNOPSIS
DESCRIPTION
       sets the real, effective and/or saved user ID of the calling process.

       If  the	current  real,	effective  or saved user ID is equal to that of a user having appropriate privileges, sets the real, effective and
       saved user IDs to ruid, euid, and suid, respectively.  Otherwise, only sets the real, effective, and saved user IDs if ruid, euid, and suid
       each match at least one of the current real, effective, or saved user IDs.

       If ruid, euid, or suid is leaves the current real, effective or saved user ID unchanged.

       sets the real, effective and/or saved group ID of the calling process.

       If  the	current  real,	effective or saved user ID is equal to that of a user having appropriate privileges, sets the real, effective, and
       saved group ID to rgid, egid, and sgid, respectively.  Otherwise, only sets the real, effective and saved group ID if rgid, egid, and  sgid
       each match at least one of the current real, effective or saved group ID.

       If rgid, egid, or sgid is leaves the current real, effective or saved group ID unchanged.

   Security Restrictions
       Some  or  all  of  the actions associated with this system call require the privilege (CHSUBJIDENT).  Processes owned by the superuser will
       have this privilege.  Processes owned by other users may have this privilege, depending on system configuration.

       See privileges(5) for more information about privileged access on systems that support fine-grained privileges.

RETURN VALUE
       Upon successful completion, and return 0; otherwise, they return -1 and set to indicate the error.

ERRORS
       and fail if any of the following conditions are encountered:

	      ruid,	     euid, or suid (rgid, egid, or sgid) is not a valid user (group) ID.

	      None of the conditions above are met.

AUTHOR
       and were developed by HP.

SEE ALSO
       exec(2), getuid(2), setuid(2), privileges(5).

																      setresuid(2)