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MMHein Author

Level 1

12 points

bash: command not found after piping

Hi,

I'm trying something quite commonly found in an Unix environment, namely piping the output of one command into the input of a subsequent one, eg.

bash$ ps ax | grep -i bash

But unfortunately I'm receiving--and now comes the most curious part--most of the times (not always!!) an error message

bash: grep: command not found

When calling grep directly

bash$ grep

the resulting output is

Usage: grep [OPTION]... PATTERN [FILE]...

Try `grep --help' for more information.

"which"-ing the commands

bash$ which bash ps grep

results in

/bin/bash

/bin/ps

/usr/bin/grep

Cheers,

MMHein

Mac mini, Mac OS X (10.7)

Posted on Jan 29, 2012 1:15 AM

32 replies

Dec 1, 2016 9:52 AM in response to MMHein

Also having had this, i just researched and came to this http://stackoverflow.com/questions/8694442/bash-piping-in-osx-prompts-command-no t-found-sometimes

If you are not on an american keyboard, and like me have to do alt + 7 to get a pipe, it happens easily that the alt is still pressed when i hit the space. This results in a so called hard space, which only looks like a space, but is not recognized by the shell. Hence the error.

Try without a space after the pipe. (or make sure you let go of alt)

DO NOT reinstall your system

Sep 6, 2017 7:30 PM in response to dancinglightning

Makes sense, will try it

bash: command not found after piping