1.\" Copyright (c) 1989, 1991, 1993 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. Neither the name of the University nor the names of its contributors 13.\" may be used to endorse or promote products derived from this software 14.\" without specific prior written permission. 15.\" 16.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 17.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 20.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26.\" SUCH DAMAGE. 27.\" 28.\" @(#)setmode.3 8.2 (Berkeley) 4/28/95 29.\" $FreeBSD$ 30.\" 31.Dd July 18, 2019 32.Dt SETMODE 3 33.Os 34.Sh NAME 35.Nm getmode , 36.Nm setmode 37.Nd modify mode bits 38.Sh LIBRARY 39.Lb libc 40.Sh SYNOPSIS 41.In unistd.h 42.Ft mode_t 43.Fn getmode "const void *set" "mode_t mode" 44.Ft void * 45.Fn setmode "const char *mode_str" 46.Sh DESCRIPTION 47The 48.Fn getmode 49function 50returns a copy of the file permission bits 51.Fa mode 52as altered by the values pointed to by 53.Fa set . 54While only the mode bits are altered, other parts of the file mode 55may be examined. 56.Pp 57The 58.Fn setmode 59function 60takes an absolute (octal) or symbolic value, as described in 61.Xr chmod 1 , 62as an argument 63and returns a pointer to mode values to be supplied to 64.Fn getmode . 65Because some of the symbolic values are relative to the file 66creation mask, 67.Fn setmode 68may call 69.Xr umask 2 . 70If this occurs, the file creation mask will be restored before 71.Fn setmode 72returns. 73If the calling program changes the value of its file creation mask 74after calling 75.Fn setmode , 76.Fn setmode 77must be called again if 78.Fn getmode 79is to modify future file modes correctly. 80.Pp 81If the mode passed to 82.Fn setmode 83is invalid or if memory cannot be allocated for the return value, 84.Fn setmode 85returns 86.Dv NULL . 87.Pp 88The value returned from 89.Fn setmode 90is obtained from 91.Fn malloc 92and should be returned to the system with 93.Fn free 94when the program is done with it, generally after a call to 95.Fn getmode . 96.Sh ERRORS 97The 98.Fn setmode 99function 100may fail and set errno for any of the errors specified for the library 101routine 102.Xr malloc 3 103or 104.Xr strtol 3 . 105In addition, 106.Fn setmode 107will fail and set 108.Va errno 109to: 110.Bl -tag -width Er 111.It Bq Er EINVAL 112The 113.Fa mode 114argument does not represent a valid mode. 115.El 116.Sh SEE ALSO 117.Xr chmod 1 , 118.Xr stat 2 , 119.Xr umask 2 , 120.Xr malloc 3 121.Sh HISTORY 122The 123.Fn getmode 124and 125.Fn setmode 126functions first appeared in 127.Bx 4.4 . 128.Sh BUGS 129The 130.Fn setmode 131function is not thread safe. 132Files created in other threads while 133.Fn setmode 134is being called may be created with a umask of 0. 135