Shell Programming and Scripting

I've tried

Code:

grep -F '---' *

to find '---' in any file but it returns

Code:

unrecognized option "---"

Does anyone know a turnaround? Found nothing in the forum nor in the man page.

---------- Post updated at 13:07 ---------- Previous update was at 13:05 ----------

And Strange
if i type

Code:

grep -F '--' *

it returns the lines in files containing '+'
That all looks like a bug.

On Solaris with /usr/xpg4/bin/grep:

Code:

jmcnama> grep  '\---' testfile
 ----------------------------------------- -------- ----------------------------
Si ---  QL>

Or:

Code:

grep -F -- '---' file

Thanks to you both. Itried by escaping every - like '\-\-\-' but didn't succeed, of course !

@Franklin52 : nothing about grep -F -- in the man page. It works, but how ? (if you know)

"--" is not a grep-specific syntax. That's a standard feature in option processing. If you need to pass an argument to a command and that argument begins with a dash, it will be interpreted as an option. To work around that scenario, "--" tells the option processing code that there are no more options to process.

You can try it yourself with different tools (rm, cp, etc). Create a file whose name begins with dash and try to pass it as an argument. It will fail to run with an unrecognized option error, if you're lucky. If you're unlucky, it will run with unintended consequences. To do it properly, you'll need to precede the filename with "--".

Guideline 10 @ Utility Conventions

For example:

Code:

$ touch -2
touch: illegal option -- 2
usage: touch [-acfm] [-r file] [-t [[CC]YY]MMDDhhmm[.SS]] file ...
$ touch -- -2
$ ls
-2
$ rm -2
rm: illegal option -- 2
usage: rm [-f | -i] [-dPRrvW] file ...
       unlink file
$ rm -- -2
$ ls
$

Hope that helped,
Alister

Thank you alister. Now i remember to having read that somewhere but had never been confronted to the necessity to use it.

Code:

grep -- --- *

works too

Code:

grep '.*---' *

Code:

sed -n /---/p *
awk /---/ *