uid_t
getuid(
void
)
uid_t
geteuid(
void
)
)
function returns the real user ID of the calling process.
The
geteuid(
)
function
returns the effective user ID of the calling process.
The real user ID is that of the user who has invoked the program.
As the effective user ID
gives the process additional permissions during
execution of
``set-user-ID''
mode processes,
getuid()
is used to determine the real-user-id of the calling process.
)
and
geteuid(
)
functions are always successful, and no return value is reserved to
indicate an error.
)
and
getuid(
)
functions conform to
ISO/IEC 9945-1:1990 (``POSIX.1'') .