How to? tpipe grep stdout?

  • This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn more.
Mar 19, 2013
Can tpipe /grep be used to grep the output of a program? My RTFM/experimentation has so far failed...

A program I run from the command line produces very verbose output, most of which I don't care about. What I'd like to do is filter this output to just the stuff I do care about.

E.g. foo.exe | tpipe /grep=3,0,0,1,0,1,1,1,"bar"

Or am I trying to use the wrong hammer?

Right hammer. And it should work. Are you sure foo.exe outputs lowercase "bar" to stdout? I wouldn't expect it to work if a program didn't write to stdout (for example, if it used WriteConsole()).

v:\> netstat | tpipe /grep=3,0,0,1,0,1,1,1,"Proto"
  Proto  Local Address          Foreign Address        State
Mar 19, 2013
Ah, tpipe processes the output after the program is finished.

And, given that, I think you are right that the program must use WriteConsole, since I see unfiltered output while the program is running.

So what I need instead I guess is some way of filtering what goes to the console (or what shows up in the scrollback buffer)...
It's somewhat odd that a console app **not** use stdout. I'd expect such an app to have a write_to_file option. If your app has such an option TPIPE could be used to process the file. If your app isn't writing to stdout, I don't think redirection (>) will help get its output into a file.

Another thought ... is it possible your app is writing to stderr?
Mar 19, 2013
Turns out it is using stdout (and stderr as well).

Interestingly, I typically run the program via a toolbar button - which, when I add the '| tpipe /grep...' to the "command", exhibits the behavior I described above (nothing filtered, everything goes to the scrollback buffer immediately).

If I instead run the program with tpipe from the prompt rather than from a button, tpipe /grep... works as expected (though not as I'd hoped) - stdout is buffered until the program exits and is then grep'd, stderr is displayed immediately.

I'd hoped to be able to filter in "realtime". But supressing/filtering stdout until exit while displaying stderr is close enough.

Thank you!