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.Dd July 18, 2019 29.Dt SETMODE 3 30.Os 31.Sh NAME 32.Nm getmode , 33.Nm setmode 34.Nd modify mode bits 35.Sh LIBRARY 36.Lb libc 37.Sh SYNOPSIS 38.In unistd.h 39.Ft mode_t 40.Fn getmode "const void *set" "mode_t mode" 41.Ft void * 42.Fn setmode "const char *mode_str" 43.Sh DESCRIPTION 44The 45.Fn getmode 46function 47returns a copy of the file permission bits 48.Fa mode 49as altered by the values pointed to by 50.Fa set . 51While only the mode bits are altered, other parts of the file mode 52may be examined. 53.Pp 54The 55.Fn setmode 56function 57takes an absolute (octal) or symbolic value, as described in 58.Xr chmod 1 , 59as an argument 60and returns a pointer to mode values to be supplied to 61.Fn getmode . 62Because some of the symbolic values are relative to the file 63creation mask, 64.Fn setmode 65may call 66.Xr umask 2 . 67If this occurs, the file creation mask will be restored before 68.Fn setmode 69returns. 70If the calling program changes the value of its file creation mask 71after calling 72.Fn setmode , 73.Fn setmode 74must be called again if 75.Fn getmode 76is to modify future file modes correctly. 77.Pp 78If the mode passed to 79.Fn setmode 80is invalid or if memory cannot be allocated for the return value, 81.Fn setmode 82returns 83.Dv NULL . 84.Pp 85The value returned from 86.Fn setmode 87is obtained from 88.Fn malloc 89and should be returned to the system with 90.Fn free 91when the program is done with it, generally after a call to 92.Fn getmode . 93.Sh ERRORS 94The 95.Fn setmode 96function 97may fail and set errno for any of the errors specified for the library 98routine 99.Xr malloc 3 100or 101.Xr strtol 3 . 102In addition, 103.Fn setmode 104will fail and set 105.Va errno 106to: 107.Bl -tag -width Er 108.It Bq Er EINVAL 109The 110.Fa mode 111argument does not represent a valid mode. 112.El 113.Sh SEE ALSO 114.Xr chmod 1 , 115.Xr stat 2 , 116.Xr umask 2 , 117.Xr malloc 3 118.Sh HISTORY 119The 120.Fn getmode 121and 122.Fn setmode 123functions first appeared in 124.Bx 4.4 . 125.Sh BUGS 126The 127.Fn setmode 128function is not thread safe. 129Files created in other threads while 130.Fn setmode 131is being called may be created with a umask of 0. 132