cuserid.3s

来自「<B>Digital的Unix操作系统VAX 4.2源码</B>」· 3S 代码 · 共 60 行

.\" SCCSID: @(#)cuserid.3s	8.1	9/11/90
.TH cuserid 3s
.SH Name
cuserid \- get character login name of the user
.SH Syntax
#include <stdio.h>
.PP
char \(**cuserid (s)
.br
char \(**s;
.SH Description
.NXR "cuserid subroutine"
.NXA "cuserid subroutine" "getlogin subroutine"
.NXR "login name" "getting character-string representation"
The
.PN cuserid
subroutine
generates a character-string representation of the login
name of the owner of the current process.
If
.I s\^
is a NULL
pointer, this representation is generated in an
internal static area, the address of which is returned.
Otherwise,
.I s\^
is assumed to point to an array of at least
.PN L_cuserid
characters; the representation is left in this array.
The constant
.PN L_cuserid
is defined in the <stdio.h> header file.
.SH Return Values
If the login name cannot be found,
.PN cuserid
returns a NULL
pointer; if 
.I s\^
is not a NULL
pointer, a null character
(\e0)
will be placed at
s[0].
.PP
In POSIX mode, 
if 
.I s\^
is not a NULL pointer, 
.I s\^
is the return value.
.SH Environment
When your program is compiled using the POSIX environment,
.PN cuserid
returns the name associated with the effective userid of the calling
process.  When compiled in the BSD or System V environments, it returns
the name associated with the login activity on the controlling terminal,
if any.  Otherwise, it returns the same as in the POSIX environment.
.SH See Also
getlogin(3), getpwent(3)