exec

The command exec executes a program and reads data from it. It supports the same syntax read does except that the program name replaces the file name. A program is a program name or anything that can be typed in a shell. If the command line has more than one string, it must be glued with quotes. On a successful call, exec will set the string constant ReadFile to the name of the program which generated the data.

exec commands assignment[range] ...

     exec simulate X:1 Y:2[0:200]
     exec "cat data | myfilter -g" X1:1[0:*] X2:2 X3:4

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