There is no pgid argument in the SYNOPSIS: patch inline and attached.
Index: setpgid.2 =================================================================== RCS file: /cvs/src/lib/libc/sys/setpgid.2,v retrieving revision 1.14 diff -u -p -r1.14 setpgid.2 --- setpgid.2 8 May 2013 14:19:44 -0000 1.14 +++ setpgid.2 24 May 2014 10:10:52 -0000 @@ -80,7 +80,7 @@ is either a session leader or not in the process. .It Bq Er EPERM The value of the -.Fa pgid +.Fa pgrp argument is neither the PID of the process indicated by the .Fa pid argument nor the process group ID of an existing process group in
patch
Description: Binary data