Add a bunch of index entries related to retrieving information from

the process table.

Doc/lib/libposix.tex

@@ -180,26 +180,32 @@ Return the current process' group id.
 \end{funcdesc}
 
 \begin{funcdesc}{getpgrp}{}
+\index{process!group}
 Return the current process group id.
 (Not on MS-DOS.)
 \end{funcdesc}
 
 \begin{funcdesc}{getpid}{}
+\index{process!id}
 Return the current process id.
 (Not on MS-DOS.)
 \end{funcdesc}
 
 \begin{funcdesc}{getppid}{}
+\index{process!id of parent}
 Return the parent's process id.
 (Not on MS-DOS.)
 \end{funcdesc}
 
 \begin{funcdesc}{getuid}{}
+\index{user id}
 Return the current process' user id.
 (Not on MS-DOS.)
 \end{funcdesc}
 
 \begin{funcdesc}{kill}{pid, sig}
+\index{process!killing}
+\index{process!signalling}
 Kill the process \var{pid} with signal \var{sig}.
 (Not on MS-DOS.)
 \end{funcdesc}