setgid.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 SETGID II 8/5/73
.sh NAME
setgid \*- set process group ID
.sh SYNOPSIS
(setgid = 46.; not in assembler)
.br
(group ID in r0)
.ft B
.br
sys setgid
.s3
setgid(gid)
.ft R
.sh DESCRIPTION
The group ID of the current process is set to
the argument.
Both the effective and the real group ID are set.
This call is only permitted to the super-user
or if the argument is the real group ID.
.sh "SEE ALSO"
getgid (II)
.sh DIAGNOSTICS
Error bit
(c-bit) is set as indicated;
from C, a \*-1 value is returned.