Subroutine:   ERROR

Purpose:      User error handling routine.

Category:     SYSTEM, USER-INTERFACE 

File:         srvreq.c

Author:       J.P. Terlouw

Use:          CALL ERROR( IER,          Input        integer
                          MESSAGE )     Input        character

              IER       Severity of error.   1 = Warning
                                             2 = Minor error
                                             3 = Serious error
                                             4 = Fatal error
              MESSAGE   Character string containing message for the
                        user.

Description:  The user is allowed to set the value of the MESSAGELEVEL
              and the ERRORLEVEL. The action taken depends on the
              severity of the error in relation to these levels.
              If IER >= ERRORLEVEL then the error is fatal and the
              task is aborted.
              If IER >= MESSAGELEVEL then the message is given to the
              user.
              Default levels: ERRORLEVEL=4, MESSAGELEVEL=1.

Examples:     With default levels IER=1,2,3 gives message but no abort.
              IER=4 gives message and aborts task
              By setting MESSAGELEVEL=2  The user or applications
              programer could suppress the error messages for IER=1
              conditions

Updates:      1978: original document
              Feb 15, 1990: JPT, Portable version, rewritten in ANSI C.