Error exit codes

z/OS UNIX FTP uses the following error exit codes:
12
Daemon initialization failed; unable to accept an incoming connection. An EZY message identifying the specific problem is sent to syslogd.
24
The client session's initialization terminated because the FTP server load module cannot be loaded or executed. Message EZYFT53E is sent to syslogd.
28
Daemon initialization was terminated because the IBM® TCP/IP is not enabled in the IFAPRDxx parmlib member. Message EZYFT54E is sent to syslogd and the operator console.