C and AWK questions

[ajs at hpfcla.UUCP]

> Does anyone know of a way to invoke a program from within AWK, passing it 
> one or more awk variables, and then trapping its output into another awk 
> variable?

The invoking part is easy; just print to a pipe.  You can print variables:

	print foo bar | echo

I don't know of a way to trap the output from the echo, however, except
perhaps in a file (which does the current awk invocation no good).

> Does anyone know how to get input from multiple files simultaneously from
> within an awk program?  

The only way I know of is ugly.  Try this:

		sep="==sep=="			# or some other pattern.

	{	cat file1
		echo $sep
		cat file2
	}	|
		awk '
		(flag == 0) {			# first file.
		    if ($0 == "'$sep'")
		    {
			flag = 1;
			next;
		    }
		    (do stuff from first file here (save data?))
		    next;
		}
		{				# second file.
		    (do stuff from second file here)
		}'