|SETREUID(2)||System Calls Manual||SETREUID(2)|
setreuid — set
real and effective user IDs
Standard C Library (libc, -lc)
The real and effective user IDs of the current process are set according to the arguments. If ruid or euid is -1, the current uid is filled in by the system. Unprivileged users may change the real user ID to the effective user ID and vice-versa; only the super-user may make other changes.
function has been used to swap the real and effective user IDs in
set-user-ID programs to temporarily relinquish the set-user-ID value. This
purpose is now better served by the use of the
function (see setuid(2)).
When setting the real and effective user IDs to the
same value, the standard
function is preferred.
setreuid() function returns the
value 0 if successful; otherwise the value -1 is returned and
the global variable errno is set to indicate the
setreuid() system call appeared in
|February 8, 2001||macOS 14.1|