43.10 Filename Headers Above Files Without pr

The pr command (43.7) displays your files with a nice header above them. But it can also add a bunch of blank lines to fill a page and break the file to add more headers in the middle if the file is longer than a page. This article shows alternatives to pr that print a single header followed by the entire file, with no extra blank lines or page breaks.

1. When you redirect the output of more (25.3) (or pg) somewhere besides a terminal, it doesn't stop at the end of a screenful. It prints a little header above each file and outputs all the files at once. Instead of redirecting the output to a file, you could pipe it to another program - like your print spooler:

   cat	% more file* > package % cat package :::::::::::::: file1 :::::::::::::: ...contents of file1.... :::::::::::::: file2 :::::::::::::: ...contents of file2.... ...

   Another way to get similar headers is a feature of head (25.20): when you give multiple filenames, it adds a header above each. To be sure head gives you all of your file (not just the head), use a line count bigger than any of your files, with a command like head -10000.

2. Bourne shell for loops with redirected output (45.22) let you combine a bunch of commands and grab the output of all of them at once. Here's a loop that runs ls -l on each file. It uses awk (33.11) to print just the file's permissions (field 1), last modification date (fields 6-8), and name (field 9, not including any name from a symbolic link). (You could pipe use more awk formatting to make a fancier heading - and get rid of the echo commands, too.) The output is redirected to a file named printme; as already stated, a pipe to your printer program will also work.

   $ for f in file*
   > do
   > echo =====================================
   > ls -l $f | awk '{print $1, $6, $7, $8, $9}'
   > echo =====================================
   > cat $f
   > done > printme
   $ cat printme
   =============================================
   -rw-r----- Oct 28 07:28 file1
   =============================================
   ...contents of file1....
   =============================================
   -r--r--r-- Nov  3 09:35 file2
   =============================================
   ...contents of file2....
   ...

If you use those last two tricks a lot, you might put them into an alias, function, or shell script (10.1).