.BR getlogin ()
returns a pointer to a string containing the name of
the user logged in on the controlling terminal of the process, or a
-null pointer if this information cannot be determined.
+NULL pointer if this information cannot be determined.
The string is
statically allocated and might be overwritten on subsequent calls to
this function or to
returns a pointer to a string containing a username
associated with the effective user ID of the process.
If \fIstring\fP
-is not a null pointer, it should be an array that can hold at least
+is not a NULL pointer, it should be an array that can hold at least
\fBL_cuserid\fP characters; the string is returned in this array.
Otherwise, a pointer to a string in a static area is returned.
This