A system call to execute a Perl script Net. This method does not allow Net. Different languages reference the variables differently. If a variable name corresponding to an output parameter is written this way, the new value replaces the current value. If a variable name is written that does not correspond to an output parameter, it is ignored.
Data performs variable substitution on the executable statements.
In this example, there are no Net. Data variables in the executable statements, so no variable substitution is performed. The external program opens the pipe as write-only and writes the values of output parameters to the pipe as if it were a standard stream file. In Example 4, the System language environment does not understand how to interpret Perl programs, but the language environment does know how to call external programs. The EXEC block tells it to call a program called perl as an external program.