chmod.2

UNIX v6源代码 这几乎是最经典的unix版本 unix操作系统设计和莱昂氏unix源代码分析都是用的该版

.th CHMOD II 12/15/74
.sh NAME
chmod \*- change mode of file
.sh SYNOPSIS
(chmod = 15.)
.br
.ft B
sys chmod; name; mode
.s3
chmod(name, mode)
.br
char *name;
.ft R
.sh DESCRIPTION
The file whose name
is given as the null-terminated string pointed to by
.it name
has its mode changed to
.it mode.
Modes are constructed by ORing together some
combination of the following:
.s3
.in +3
 4000 set user ID on execution
 2000 set group ID on execution
 1000 save text image after execution
 0400 read by owner
 0200 write by owner
 0100 execute (search on directory) by owner
 0070 read, write, execute (search) by group
 0007 read, write, execute (search) by others
.in -3
.s3
Only the owner of a file (or the super-user) may change the mode.
Only the super-user can set the 1000 mode.
.sh "SEE ALSO"
chmod (I)
.sh DIAGNOSTIC
Error bit
(c-bit) set if
.it name
cannot be found or if current user
is neither the owner of the file nor the super-user.
From C, a \*-1 returned value indicates an
error, 0 indicates success.