[unix-history] / usr / man / man2 / access.2

.TH ACCESS 2 
.SH NAME
access \- determine accessibility of file
.SH SYNOPSIS
.B access(name, mode)
.br
.B char *name;
.SH DESCRIPTION
.I Access
checks the given
file
.I name
for accessibility according to
.I mode,
which is 4 (read), 2 (write) or 1 (execute) or a combination thereof.
Specifying mode 0
tests whether the directories leading to the file can be
searched and the file exists.
.PP
An appropriate error indication is returned if 
.I name
cannot be found or if any
of the desired access modes would not be granted.
On disallowed accesses
\-1 is returned and the error code is in
.IR errno .
0 is returned from successful tests.
.PP
The user and group IDs with respect to which permission is checked
are the real UID and GID of the process, so this call is
useful to set-UID programs.
.PP
Notice that it is only access bits that are checked.
A directory may be announced as writable by
.I access,
but an attempt to open it for writing will fail
(although files may be created there);
a file may look executable, but
.I exec
will fail unless it is in proper format.
.PP
.SH SEE ALSO
stat(2)
.SH "ASSEMBLER (PDP-11)"
(access = 33.)
.br
.B sys access; name; mode
Commit	Line	Data
e6817382 BJ	1	.TH ACCESS 2
	2	.SH NAME
	3	access \- determine accessibility of file
	4	.SH SYNOPSIS
	5	.B access(name, mode)
	6	.br
	7	.B char *name;
	8	.SH DESCRIPTION
	9	.I Access
	10	checks the given
	11	file
	12	.I name
	13	for accessibility according to
	14	.I mode,
	15	which is 4 (read), 2 (write) or 1 (execute) or a combination thereof.
	16	Specifying mode 0
	17	tests whether the directories leading to the file can be
	18	searched and the file exists.
	19	.PP
	20	An appropriate error indication is returned if
	21	.I name
	22	cannot be found or if any
	23	of the desired access modes would not be granted.
	24	On disallowed accesses
	25	\-1 is returned and the error code is in
	26	.IR errno .
	27	0 is returned from successful tests.
	28	.PP
	29	The user and group IDs with respect to which permission is checked
	30	are the real UID and GID of the process, so this call is
	31	useful to set-UID programs.
	32	.PP
	33	Notice that it is only access bits that are checked.
	34	A directory may be announced as writable by
	35	.I access,
	36	but an attempt to open it for writing will fail
	37	(although files may be created there);
	38	a file may look executable, but
	39	.I exec
	40	will fail unless it is in proper format.
	41	.PP
	42	.SH SEE ALSO
	43	stat(2)
	44	.SH "ASSEMBLER (PDP-11)"
	45	(access = 33.)
	46	.br
	47	.B sys access; name; mode