How to remove line that begins with three #
For example need to delete all the following lines: from file
1 ### bla bla bal
2 ###blablabla
3 ### blabla
. . .
THX Yael
+1, except that there is no need for cat ;)
unbeli
2010-06-22 10:33:22
Well if you try it without it will sit there for a long time ;)
Steve Weet
2010-06-22 10:42:50
you pass the file as input to sed. `sed '/^###/d' file`
ghostdog74
2010-06-22 10:58:03
We could get into a long discussion of how *nix scripts should always be pipes from STDIN/STDOUT but yes, sed will take one or more file arguments on the command line.
Steve Weet
2010-06-22 11:24:25
@Steve sed '/^###/d' < file
unbeli
2010-06-22 11:46:33
from my point its better to use the awk but how to change sed in order to do what awk do?
yael
2010-06-22 12:10:54
for example cat file | sed '/^###/d' not effect if some space before the "###"yael
yael
2010-06-22 12:11:47
@unbeli, and there's no need for input redirection
ghostdog74
2010-06-22 12:38:36
@ghostdog74 and there is no need to repeat yourself ;)
unbeli
2010-06-22 12:50:15
@unbeli, what are you referring to? i am talking about the "<" in `sed ... < file` that you propose. This is technically not the same as `cat file| sed ...`. so which part am i repeating myself?
ghostdog74
2010-06-22 13:57:53
@ghostdog74 how is sed < file different from cat file | sed, except sparing some time?
unbeli
2010-06-22 14:41:17
@yael. The reason this does not remove lines beginning with spaces or tabs followed by ### is that this was not asked for. You can do that with `sed '/^[\t ]*###/d'` the same as the awk command.
Steve Weet
2010-06-22 16:35:45
@everyone. Can we please accept that sed will read input from STDIN (Whether piped or redirected) or from one or more filenames provided as paramaters on the command line. This comment thread is getting silly
Steve Weet
2010-06-22 16:37:27