common/man/strperm.3

        .fp 5 CW
..
.nr ;G \\n(.f
.Af "\\$1" "\\$2" "\\$3" "\\$4" "\\$5" "\\$6" "\\$7" "\\$8" "\\$9"
\\*(;G
..
.aF 5 \\n(.f "\\$1" "\\$2" "\\$3" "\\$4" "\\$5" "\\$6" "\\$7"
..
.aF 5 1 "\\$1" "\\$2" "\\$3" "\\$4" "\\$5" "\\$6" "\\$7"
..
.aF 1 5 "\\$1" "\\$2" "\\$3" "\\$4" "\\$5" "\\$6" "\\$7"
..


 0
..


..
 STRPERM 3
 NAME
strperm - evaluate file permission expression
 SYNOPSIS
.L "int strperm(char* s, char** e, int p)"
 DESCRIPTION
 strperm applies a file permission expression in the nul-terminated string
 s to the initial file permission mask
 p . The new permission mask is returned.
If
 e not 0 then
 *e is set to point to the first unrecognized character in
 s .
A tape device specification is composed of one or more
 who-op-permission terms separated by
 , .  who selects portions of the permission bits and may be any combination of:
 3
 u the user permission bits;

 g the group permission bits;

 o the `other' permission bits;

 a all permission bits.

If omitted, all permission bits are selected.
 op specifies how the original permission
 p is to be modified:
 3
 +
.ns
 | the new bits are set in
 p ;  3
 - the new bits are cleared in
 p ;
 & the new bits are and'd with
 p ;
 = the select bits in
 p are set equal to the new bits

A permission expression term may also be an octal number.
Octal specifications are inherently non-portable.
Refer to
 chmod (1) for an explanation of this form.
 "SEE ALSO"
chmod(1), ls(1), strmode(3)