1.4. Executing Rexx programs with Regina Rexx programs are generally executed by Regina for the command line in the following manner: regina [switches] [program] [program parameters] where: regina is the name of the Regina executable (see table above) switches are optional switches. See the section below for an explanation of the switches currently supported by Regina program the name of the Rexx program to be executed. See the section External Rexx Programs, below, for details on how Regina interprets this argument. If no program name is specified, Regina waits for Rexx commands to be typed in and will execute those commands when the appropriate end-of-file character (^D on Unix and ^Z on DOS, OS/2 and Windows NT/95) is typed. program parameters any optional parameters to be passed to the Rexx program. Rexx programs to be executed by Regina can take advantage of a feature of Unix shell programs called magic numbers. By having the first line of a Rexx program consist of the special sequence of #! followed by the full file name of the Regina executable, you can invoke this program simply by typing the name of the Rexx program on the command line followed by any parameters you wish to pass to the Rexx program. The file name must also have the appropriate execute bit set for this to work. As an example suppose your Rexx program, myprog, contained: #!/usr/local/bin/regina Parse Version ver Say ver When executing this program from the command line by typing myprog, the Unix shell program would execute the program /usr/local/bin/regina and pass the remainder of the lines in the file to this program via stdin. The special processing done by Regina to find the file name in REGINA_MACROS and the file extension searching is not able to be carried out when using the magic number method of invocation.