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GETUID(2)                   BSD System Calls Manual                  GETUID(2)

NAME
     geteuid, getuid -- get user identification

SYNOPSIS
     #include <unistd.h>

     uid_t
     geteuid(void);

     uid_t
     getuid(void);

DESCRIPTION
     The getuid() 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.

ERRORS
     The getuid() and geteuid() functions are always successful, and no return value is reserved to indicate
     an error.

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

     The include file <sys/types.h> is necessary for both functions.

SEE ALSO
     getgid(2), setreuid(2), compat(5)

STANDARDS
     Geteuid() and getuid() functions conform to IEEE Std 1003.1-1988 (``POSIX.1'').

4th Berkeley Distribution        June 4, 1993        4th Berkeley Distribution