I am using grep like this:
grep -r "foo" * > output.txt
However it seems grep is constantly picking up results from output.txt which grows indefinitely. How can I prevent this from happening?
See man grep. Then try this:
grep -r "foo" * --exclude=output.txt > output.txt
One solution is :
grep -r "foo" . > ../output.txt
^^
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I want the output of the sed file edit to go into my log file name d_selinuxlog.txt. Currently, grep outputs the specified string as well as 3 other strings above and below in the edited file.
#!/bin/bash
{ getenforce;
sed -i s/SELINUX=enforcing/SELINUX=disabled /etc/selinux/config;
grep "SELINUX=*" /etc/selinux/config > /home/neb/scropts/logs/d_selinuxlog.txt;
setenforce 0;
getenforce; }
I want to be seeing just SELINUX=disabled in the log file
All the lines with the lines SELINUX are going to match, even the commented ones, so, you need to omit that ones, and the * from the match.
grep "SELINUX=" /etc/selinux/config | grep -v "#"
This is my output
17:52:07 alvaro#lykan /home/alvaro
$ grep "SELINUX=" /etc/selinux/config | grep -v "#"
SELINUX=disabled
17:52:22 alvaro#lykan /home/alvaro
I want to print the filename if only ALL the matches are present... on different lines
grep -l -w '10B\|01A\|gencode' */$a*filename.vcf
this prints out the filename, but not only if ALL three matches are present.
Would you consider to try awk? awk may solve it in following method,
awk '/10B/&&/01A/&&/gencode/{print FILENAME}' */$a*filename.vcf
try following, just edited your solution a bit.
grep -l '10B.*01A.*gencode' Input_file
With grep and its -P (Perl-Compatibility) option and positive lookahead regex (?=(regex)), to match patterns if in any order.
grep -lwP '(?=.*?10B)(?=.*?01A)(?=.*?gencode)' /path/to/infile
grep -l 'pattern1' files ... | xargs grep -l 'pattern2' | xargs grep -l 'pattern3'
From the grep manual:
-l, --files-with-matches
Suppress normal output; instead print the name of each input file from which output would normally have been printed. The scanning will stop on the first match. (-l is specified by POSIX.)
How can I show the count of a grep per file when searching in various files at once via regex
grep -c -? somestring log*
so, if I have n files log_1, log_2, log_3, .., log_n and I grep -c for somestring, then I would like the output to be
log_1 'result of grep -c in file log_1'
log_2 'result of grep -c in file log_2'
Can I do this with a grep command or do I have to construct some sort of loop?
From almas shaik. works great
grep -cH <searchString> <files>
I use grep -L to get a list of files that do not contain a certain string. How can I see the content of those files? Just like:
grep -L "pattern" | cat
You can use xargs:
grep -L "pattern" | xargs cat
As read in man xargs --> build and execute command lines from standard input. So it will cat to those file names that grep -L returns.
You can use cat and use the output of grep -L...
cat $(grep -L "pattern" *.files )
I want to grep -R a directory but exclude symlinks how dow I do it?
Maybe something like grep -R --no-symlinks or something?
Thank you.
Gnu grep v2.11-8 and on if invoked with -r excludes symlinks not specified on the command line and includes them when invoked with -R.
If you already know the name(s) of the symlinks you want to exclude:
grep -r --exclude-dir=LINK1 --exclude-dir=LINK2 PATTERN .
If the name(s) of the symlinks vary, maybe exclude symlinks with a find command first, and then grep the files that this outputs:
find . -type f -a -exec grep -H PATTERN '{}' \;
The '-H' to grep adds the filename to the output (which is the default if grep is searching recursively, but is not here, where grep is being handed individual file names.)
I commonly want to modify grep to exclude source control directories. That is most efficiently done by the initial find command:
find . -name .git -prune -o -type f -a -exec grep -H PATTERN '{}' \;
For now.. here is how I would exclude symbolic links when using grep
If you want just file names matching your search:
for f in $(grep -Rl 'search' *); do if [ ! -h "$f" ]; then echo "$f"; fi; done;
Explaination:
grep -R # recursive
grep -l # file names only
if [ ! -h "file" ] # bash if not a symbolic link
If you want the matched content output, how about a double grep:
srch="whatever"; for f in $(grep -Rl "$srch" *); do if [ ! -h "$f" ]; then
echo -e "\n## $f";
grep -n "$srch" "$f";
fi; done;
Explaination:
echo -e # enable interpretation of backslash escapes
grep -n # adds line numbers to output
.. It's not perfect of course. But it could get the job done!
If you're using an older grep that does not have the -r behavior described in Aryeh Leib Taurog's answer, you can use a combination of find, xargs and grep:
find . -type f | xargs grep "text-to-search-for"
If you are using BSD grep (Mac) the following works similar to '-r' option of Gnu grep.
grep -OR <PATTERN> <PATH> 2> /dev/null
From man page
-O If -R is specified, follow symbolic links only if they were explicitly listed on the command line.