GETUID(2) NetBSD System Calls Manual GETUID(2)
getuid, geteuid -- get user identification
Standard C Library (libc, -lc)
#include <unistd.h> uid_t getuid(void); uid_t geteuid(void);
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 execu- tion of ``set-user-ID'' mode processes, getuid() is used to determine the real-user-id of the calling process.
The getuid() and geteuid() functions are always successful, and no return value is reserved to indicate an error.
The geteuid() and getuid() functions conform to ISO/IEC 9945-1:1990 (``POSIX.1'').
The getuid() function appeared in Version 4 AT&T UNIX. NetBSD 8.1 April 3, 2010 NetBSD 8.1
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