Examples

   1.$ COUNT = 0
     $ LOOP:
     $ COUNT = COUNT + 1
        .
        .
        .
     $ IF COUNT .LE. 10 THEN GOTO LOOP
     $ EXIT

     This example shows how to establish a loop in a command
     procedure, using a symbol named COUNT and an IF statement.
     The IF statement checks the value of COUNT and performs an EXIT
     command when the value of COUNT is greater than 10.

   2.$ IF P1 .EQS. "" THEN GOTO DEFAULT
     $ IF (P1 .EQS. "A") .OR. (P1 .EQS. "B") THEN GOTO 'P1'
     $ WRITE SYS$OUTPUT "Unrecognized parameter option ''P1' "
     $ EXIT
     $ A:       !  Process option a
      .
      .
      .
     $ EXIT
     $ B:       !  Process option b
      .
      .
      .
     $ EXIT
     $ DEFAULT: !  Default processing
      .
      .
      .
     $ EXIT

     This example shows a command procedure that tests whether a
     parameter was passed. The GOTO command passes control to the
     label specified as the parameter.

     If the procedure is executed with a parameter, the procedure
     uses that parameter to determine the label to branch to. For
     example:

       @TESTCOM A

     When the procedure executes, it determines that P1 is not null,
     and branches to the label A. Note that the EXIT command causes
     an exit from the procedure before the label B.

   3.$  SET NOON
      .
      .
      .
     $  LINK CYGNUS,DRACO,SERVICE/LIBRARY
     $ IF $STATUS
     $ THEN
     $  RUN CYGNUS
     $ ELSE
     $   WRITE SYS$OUTPUT "LINK FAILED"
     $ ENDIF
     $ EXIT

     This command procedure uses the SET NOON command to disable
     error checking by the command procedure. After the LINK
     command, the IF command tests the value of the reserved global
     symbol $STATUS. If the value of $STATUS indicates that the LINK
     command succeeded, then the program CYGNUS is run. If the LINK
     command returns an error status value, the command procedure
     issues a message and exits.

   4.$ if 1 .eq. 1
     $ then
     $   if 2 .eq. 2
     $   then
     $     write sys$output  "Hello!"
     $   endif
     $ endif

     This example shows how to use a nested IF structure.