I'm trying to grep for a string that starts with "--"
for some reason it counted as special character, but even when trying to use -F then grep gives me bad syntax:
[root#pc-01 /]# grep -F --restore .
-bash: --restore: command not found
any tips?
Thanks.
Try following.
grep -F -- --restore filename
You can escape the first - :
Without escaping:
[root#TIAGO-TEST2 tmp]# echo '--aa --bb --cc' | grep -o '--b'
grep: option '--b' is ambiguous; possibilities: '--basic-regexp' '--binary' '--byte-offset' '--binary-files' '--before-context'
Usage: grep [OPTION]... PATTERN [FILE]...
Try `grep --help' for more information.
Escaping:
[root#TIAGO-TEST2 tmp]# echo '--aa --bb --cc' | grep -o '\--b'
--b
Related
I'm trying to find lines that start with 'query' or the following sign: '>' but I don't know how to do this.
If this is the dataset:
query=345
query=4565
brink=980
>ehlhdhdk
>blonk
I want to only preserve the lines 1,2,4 and 5.
I have tried: grep -e 'query=' filename.txt||grep -F '>' filename.txt > newfile.txt
and:
cat filename.txt | grep -e 'query='||grep -F '>' > newfile.txt.
But these do not work and they do not output the newfile.txt and instead they just output into the terminal.
You can use
grep -E '^(query|>)' filename.txt > newfile.txt
Details
^ - start of string
(query|>) - a capturing group that matches either
query - query
| - or
> - a > char.
See the online demo:
#!/bin/bash
s='query=345
query=4565
brink=980
>ehlhdhdk
>blonk'
grep -E '^(query|>)' <<< "$s"
Output:
query=345
query=4565
>ehlhdhdk
>blonk
Use multiple patterns with option -e:
grep -e '^>' -e '^query' file
Output:
query=345
query=4565
>ehlhdhdk
>blonk
Team,
I want to grep for a substring container - and then only output that string and not whole line. how can i? I know i can awk on space and pull using $ but want to know how to do in grep?
echo $test_pods_info | grep -F 'test-'
output
test-78ac951e-89a6-4199-87a4-db8a1b8b054f export-9b55f0d5-071d-431-1d2ux0-avexport-xavierisp-sjc4--a4dd85-102 1/1 Running 0 19h
expected output
test-78ac951e-89a6-4199-87a4-db8a1b8b054f
awk is more suitable for this as you want to get first field in a matching line:
awk '/test-/{print $1}' <<< "$taxIncluded"
test-78ac951e-89a6-4199-87a4-db8a1b8b054f
If you really want to use grep then this might be what you're looking for:
grep -o 'test-\S*' <<< "$taxIncluded"
or:
grep -o 'test-[^[:space:]]*' <<< "$taxIncluded"
Try
echo $test_pods_info | grep -o 'test-'
the -o option is:
show[ing] only the part of a line matching PATTERN
according to grep --help. Of course, this will only print test-, so you'll need to rework your regex:
grep -oE '(test).*[[:space:]]\b'
Figured it out..
echo $test_pods_info | grep -o "\test-\w*-\w*\-\w*\-\w*\-\w*"
outoput
test-78ac951e-89a6-4199-87a4-db8a1b8b054f
but i wish there is simple way. like \test-*\
I want to print the filename if only ALL the matches are present... on different lines
grep -l -w '10B\|01A\|gencode' */$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.)
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.