Redirect STDIN

< /path/to/file.txt grep foo
Several times, I find myself hitting my up arrow, and changing the search term. Unfortunately, I find myself wasting too much time typing: grep kernel /var/log/messages Redirecting STDIN allows me to put the search term at the end so I less cursor movement to change what I'm searching for: < /var/log/messages grep kernel If you're using the emacs keyboard binding, then after you press your up arrow, press CTRL+w to erase the word. If this has already been submitted, I couldn't find it with the search utility.

15
By: atoponce
2009-03-29 02:43:40

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What Others Think

very nice. I had not thought of that
GNUix · 481 weeks and 2 days ago
This is very nice. I had always used cat file|grep foo for easy editing. Good to know there's a better syntax.
clockworkavian · 481 weeks and 2 days ago
grep foo
jnash · 481 weeks and 2 days ago
I wanted to say: grep foo
jnash · 481 weeks and 2 days ago
Oh well.. looks like theres some garbling of comments. (here goes) I wanted to say: grep foo "lessthan"(cat file)
jnash · 481 weeks and 2 days ago
clockworkavian: using grep with cat like that is highly discouraged, as it (needlessly) invokes cat. I like the suggestion for redirecting stdin.
kaedenn · 481 weeks and 1 day ago
@kaedenn I know it's discouraged, as grep can do it natively, but for long filenames, having to hit the arrow keys a bunch of times to change a search term is a pain. I will follow the correct way when it involves less work (the redirection is acceptable), but when it involves more work, I think I'll do it wrong and cut down the RSI
clockworkavian · 481 weeks ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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