C
  SYNOPSIS  
   #include <pcp/pmapi.h>  
 pmSetProcessIdentity(const char * username ); 
 cc ... -lpcp 
 
  DESCRIPTION  
   pmSetProcessIdentity  provides a platform-independent method
    to set the user id of a process to that matching  username . 
 If possible (when the caller is already running as root)
     pmSetProcessIdentity  will set the group id of the process to that of
    the matching user, e.g. using  username  and   getpwnam (3) . 
 A return value of 0 indicates success, otherwise the return value
    is an error code that may be decoded with   pmErrStr (3) . 
  pmSetProcessIdentity  is most often used in conjunction with
      pmGetUsername (3)  at process start up. 
 
  SEE
  ALSO  
    getpwnam (3) ,   PMAPI (3) ,   pmErrStr (3) ,
      pmGetUsername (3) ,   setgid (3)  and   setuid (3) .