exit - End the application

       Terminate  the  process,  returning  returnCode  to  the system as the exit status.  If returnCode is not
       specified then it defaults to 0.

       Since non-zero exit codes are usually interpreted as error cases by the calling process, the exit command
       is an important part of signaling that something fatal has gone wrong. This code fragment  is  useful  in
       scripts to act as a general problem trap:

              proc main {} {
                  # ... put the real main code in here ...
              }

              if {[catch {main} msg options]} {
                  puts stderr "unexpected script error: $msg"
                  if {[info exists env(DEBUG)]} {
                      puts stderr "---- BEGIN TRACE ----"
                      puts stderr [dict get $options -errorinfo]
                      puts stderr "---- END TRACE ----"
                  }

                  # Reserve code 1 for "expected" error exits...
                  exit 2
              }

       abort, exit, process

Tcl                                                                                                   exit(3tcl)

       exit - End the application

exec(3tcl)

exit ?returnCode?
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