[apple/libc.git] / gen / FreeBSD / setmode.3

.\" Copyright (c) 1989, 1991, 1993
.\"	The Regents of the University of California.  All rights reserved.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\"    notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\"    notice, this list of conditions and the following disclaimer in the
.\"    documentation and/or other materials provided with the distribution.
.\" 3. All advertising materials mentioning features or use of this software
.\"    must display the following acknowledgement:
.\"	This product includes software developed by the University of
.\"	California, Berkeley and its contributors.
.\" 4. Neither the name of the University nor the names of its contributors
.\"    may be used to endorse or promote products derived from this software
.\"    without specific prior written permission.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
.\" SUCH DAMAGE.
.\"
.\"     @(#)setmode.3	8.2 (Berkeley) 4/28/95
.\" $FreeBSD: src/lib/libc/gen/setmode.3,v 1.11 2001/10/01 16:08:51 ru Exp $
.\"
.Dd April 28, 1995
.Dt SETMODE 3
.Os
.Sh NAME
.Nm getmode ,
.Nm setmode
.Nd modify mode bits
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In unistd.h
.Ft mode_t
.Fn getmode "const void *set" "mode_t mode"
.Ft void *
.Fn setmode "const char *mode_str"
.Sh DESCRIPTION
The
.Fn getmode
function
returns a copy of the file permission bits
.Fa mode
as altered by the values pointed to by
.Fa set .
While only the mode bits are altered, other parts of the file mode
may be examined.
.Pp
The
.Fn setmode
function
takes an absolute (octal) or symbolic value, as described in
.Xr chmod 1 ,
as an argument
and returns a pointer to mode values to be supplied to
.Fn getmode .
Because some of the symbolic values are relative to the file
creation mask,
.Fn setmode
may call
.Xr umask 2 .
If this occurs, the file creation mask will be restored before
.Fn setmode
returns.
If the calling program changes the value of its file creation mask
after calling
.Fn setmode ,
.Fn setmode
must be called again if
.Fn getmode
is to modify future file modes correctly.
.Pp
If the mode passed to
.Fn setmode
is invalid or if memory cannot be allocated for the return value,
.Fn setmode
returns
.Dv NULL .
.Pp
The value returned from
.Fn setmode
is obtained from
.Fn malloc
and should be returned to the system with
.Fn free
when the program is done with it, generally after a call to
.Fn getmode .
.Sh ERRORS
The
.Fn setmode
function
may fail and set errno for any of the errors specified for the library
routine
.Xr malloc 3 .
.Sh SEE ALSO
.Xr chmod 1 ,
.Xr stat 2 ,
.Xr umask 2 ,
.Xr malloc 3
.Sh HISTORY
The
.Fn getmode
and
.Fn setmode
functions first appeared in
.Bx 4.4 .
Commit	Line	Data
5b2abdfb	1	.\" Copyright (c) 1989, 1991, 1993
e9ce8d39 A	2	.\" The Regents of the University of California. All rights reserved.
	3	.\"
	4	.\" Redistribution and use in source and binary forms, with or without
	5	.\" modification, are permitted provided that the following conditions
	6	.\" are met:
	7	.\" 1. Redistributions of source code must retain the above copyright
	8	.\" notice, this list of conditions and the following disclaimer.
	9	.\" 2. Redistributions in binary form must reproduce the above copyright
	10	.\" notice, this list of conditions and the following disclaimer in the
	11	.\" documentation and/or other materials provided with the distribution.
	12	.\" 3. All advertising materials mentioning features or use of this software
	13	.\" must display the following acknowledgement:
	14	.\" This product includes software developed by the University of
	15	.\" California, Berkeley and its contributors.
	16	.\" 4. Neither the name of the University nor the names of its contributors
	17	.\" may be used to endorse or promote products derived from this software
	18	.\" without specific prior written permission.
	19	.\"
	20	.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	21	.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	22	.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	23	.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	24	.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	25	.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	26	.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	27	.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	28	.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	29	.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	30	.\" SUCH DAMAGE.
	31	.\"
5b2abdfb	32	.\" @(#)setmode.3 8.2 (Berkeley) 4/28/95
9385eb3d	33	.\" $FreeBSD: src/lib/libc/gen/setmode.3,v 1.11 2001/10/01 16:08:51 ru Exp $
e9ce8d39	34	.\"
5b2abdfb A	35	.Dd April 28, 1995
5b2abdfb A	36	.Dt SETMODE 3
e9ce8d39 A	37	.Os
e9ce8d39 A	38	.Sh NAME
5b2abdfb A	39	.Nm getmode ,
	40	.Nm setmode
	41	.Nd modify mode bits
e9ce8d39 A	42	.Sh LIBRARY
	43	.Lb libc
	44	.Sh SYNOPSIS
5b2abdfb A	45	.In unistd.h
	46	.Ft mode_t
	47	.Fn getmode "const void *set" "mode_t mode"
	48	.Ft void *
	49	.Fn setmode "const char *mode_str"
e9ce8d39 A	50	.Sh DESCRIPTION
e9ce8d39 A	51	The
5b2abdfb A	52	.Fn getmode
	53	function
	54	returns a copy of the file permission bits
	55	.Fa mode
	56	as altered by the values pointed to by
	57	.Fa set .
	58	While only the mode bits are altered, other parts of the file mode
	59	may be examined.
	60	.Pp
e9ce8d39	61	The
5b2abdfb A	62	.Fn setmode
	63	function
	64	takes an absolute (octal) or symbolic value, as described in
	65	.Xr chmod 1 ,
	66	as an argument
	67	and returns a pointer to mode values to be supplied to
	68	.Fn getmode .
	69	Because some of the symbolic values are relative to the file
	70	creation mask,
	71	.Fn setmode
	72	may call
	73	.Xr umask 2 .
	74	If this occurs, the file creation mask will be restored before
	75	.Fn setmode
	76	returns.
	77	If the calling program changes the value of its file creation mask
	78	after calling
	79	.Fn setmode ,
	80	.Fn setmode
	81	must be called again if
	82	.Fn getmode
	83	is to modify future file modes correctly.
	84	.Pp
	85	If the mode passed to
	86	.Fn setmode
	87	is invalid or if memory cannot be allocated for the return value,
	88	.Fn setmode
	89	returns
	90	.Dv NULL .
	91	.Pp
	92	The value returned from
	93	.Fn setmode
	94	is obtained from
	95	.Fn malloc
	96	and should be returned to the system with
	97	.Fn free
	98	when the program is done with it, generally after a call to
	99	.Fn getmode .
e9ce8d39	100	.Sh ERRORS
5b2abdfb A	101	The
	102	.Fn setmode
	103	function
	104	may fail and set errno for any of the errors specified for the library
	105	routine
	106	.Xr malloc 3 .
e9ce8d39	107	.Sh SEE ALSO
5b2abdfb A	108	.Xr chmod 1 ,
	109	.Xr stat 2 ,
	110	.Xr umask 2 ,
	111	.Xr malloc 3
e9ce8d39 A	112	.Sh HISTORY
e9ce8d39 A	113	The
5b2abdfb A	114	.Fn getmode
	115	and
	116	.Fn setmode
	117	functions first appeared in
e9ce8d39	118	.Bx 4.4 .