Hi Robin,
With pipe buffering, I don't think there is any guarantee that the output from the echo or from xargs -t sent to STDERR won't appear on the screen before some output from grep of the previous archive. And the same thing could happen if you try to capture both STDOUT and STDERR and redirect them to a single output file.

To get the name of the archive being processed in the standard output stream and survive the grep in the pipeline, one might try something more like:

Code:

for targz in *.tar.gz
do
   echo "folder1/folder2 files in $targz..."   # Write to STDOUT so script output can be redirected
   tar -tf $targz
done | grep folder1/folder2

As RudiC mentioned, some versions of tar will get lost if given a zipped archive. But, assuming that the tar on april's system gunzips a file automatically if its name ends in .gz, this should work.