Re: gawk exit doesn't exit promptly

[Jürgen Kahrs]

Andrew J. Schorr schrieb:
> On Fri, Jan 02, 2009 at 12:59:23PM -0500, Boemker, Tim wrote:
>> $ cat a
>> a
>> $ tail -f a | gawk '{ print "exiting"; exit }'
>> exiting
> 
> I tried on my machine, and gawk exits fine.  I think you
> may be unhappy because the "tail -f" command does not
> exit.  As a result, the command keeps waiting.  If you
> go into another shell and run "echo b >> a", then you
> will see that the entire pipeline will exit because
> the "tail -f" command will get a SIGPIPE when it tries
> to write to the nonexistent gawk process.

Andrew is right here. Don't use the -f and it will work.

Apart from this, I vaguely remember that Kernighan's
original AWK really needed the "exit" when printing
after BEGIN. That's the reason why some peopler today
still insist that a "Hello, world" program in AWK
has to look like this:

  http://helloworldsite.he.funpic.de/hello.htm#awk

BEGIN {
  print "Hello World!"
  exit
}

Old AWK interpreters like Solaris oawk really need the
"exit", while modern implementations don't need it.
But, remember, the OP asked about something different.