.TH CHGRP 1 .SH NAME chgrp \- change file group .SH SYNOPSIS .B chgrp [ .B -ou ] .I group file ... .SH DESCRIPTION The group of each named file is changed to .IR group , which should be a name known to the server holding the file. .PP A file's group can be changed by the file's owner, if the owner is a member of the new group, or by the leader of both the file's current group and the new group. .PP The .B -o and .B -u option are synonyms; they specify that the .I owner is to be set, rather than the group. They are ineffectual unless the file server is in the bootstrap state that permits changing file ownership. .SH SOURCE .B /sys/src/cmd/chgrp.c .SH "SEE ALSO" .IR ls (1), .IR chmod (1), .IR stat (2)