I wanted to search for this particular string $string['site:config'] in my folder. But when I use a normal grep function grep -r "$string['site:config']" it gives me random results.
The problem with your pattern is that characters like $ [ ] are characters used to define regular expressions and you have either to escape them:
grep "\$string\['site:config'\]"
or instruct grep to look for the given string as is:
grep -F "$string['site:config']"
without attempting to interpret it as a regular expression.
Related
I am trying to list files in a specific directory whose name do not match a certain pattern.
For eg. list all files not ending with abc.yml
For this I am using the command:
ls | grep -v "*abc.yml"
However I still see the files ending with abc.yml, what am I doing wrong here?
Asterisk has a different meaning in regular expressions. In fact, putting it to the front of the expressions makes it match literally. You can remove it, as grep tries to match the expression anywhere on the line, it doesn't try to match the whole line. To add the "end of line" anchor, add $. Also, . matches any character, use \. to match a dot literally:
ls | grep -v 'abc\.yml$'
In some shells, you can use extended globbing to list the files without the need to pipe to grep. For example, in bash:
shopt -s extglob
ls !(*abc.yml)
Below is the string I am trying to grep for this in the bash shell:
'#Hostname=sometext.company.com, sometext.company.com' filename
I want to only find the string if it matches that exact pattern. I already tried the command below and a few others.
grep -Fx "#Hostname=sometext.company.com, sometext.company.com" filename
Did you specify the -xoption on purpose?
grep -F '#Hostname=sometext.company.com, sometext.company.com' filename
most likely is what you want. Also, it's better to put single quotes instead of double quotes, just in case your search pattern happens to contain special shell characters.
I am trying grep some string in a script.
I don't know what string i am finding or what is in file where I am trying to find it. I just need grep exact string from file.
So, my problem is, sometimes greping string contains square brackets and as I found out, grep consider them special characters.
string='some [text]'
grep "$string" file
I can escape them with sed
string='some [text]'
grep "$(sed -e 's/\[/\\[/g' <<< "$string")" file
I need grep to match exact string no matter what input can be. So is there a nicer way to do it? some way to tell grep to consider every character in string as regular character? If no, are there any other special characters like [ I need to worry about?
You can use -F option, to interpret it as fixed string:
grep -F "$string" file
I am trying to find alphanumeric string including these two characters "/+" with at least 30 characters in length.
I have written this code,
grep "[a-zA-Z0-9\/\+]{30,}" tmp.txt
cat tmp.txt
> array('rWmyiJgKT8sFXCmMr639U4nWxcSvVFEur9hNOOvQwF/tpYRqTk9yWV2xPFBAZwAPRVs/s
ddd73ZEjfy+airfy8DtqIqKI9+dd 6hdd7soJ9iG0sGs/ld5f2GHzockoYHfh
+pAzx/t17Crf0T/2+8+reo+MU39lqCr02sAkcC1k/LzyBvSDEtu9N/9NHicr jA3SvDqg5s44DFlaNZ/8BW37fGEf2rk13S/q68OVVyzac7IT7yE7PIL9XZ/6LsmrY
KEsAmN4i/+ym8be3wwn KWGYaIB908+7W98pI6qao3iaZB
3mh7Y/nZm52hyLa37978f+PyOCqUh0Wfx2PL3vglofi0l
QVrOM1pg+mFLEIC88B706UzL4Pss7ouEo+EsrES+/qJq9Y1e/UGvwefOWSL2TJdt
this does not work, Mainly I wanted to have minimum length of the string to be 30
In the syntax of grep, the repetition braces need to be backslashed.
grep -o '[a-zA-Z0-9/+]\{30,\}' file
If you want to constrain the match to lines containing only matches to this pattern, add line-start and line-ending anchors:
grep '^[a-zA-Z0-9/+]\{30,\}$' file
The -o option in the first command line causes grep to only print the matching part, not the entire matching line.
The repetition operator is not directly supported in Basic Regular Expression syntax. Use grep -E to enable Extended Regular Expression syntax, or backslash the braces.
You can use
grep -e "^[a-zA-Z0-9/+]\{30,\}" tmp.txt
grep -e "^[a-zA-Z0-9/+]\{30,\}" tmp.txt
+pAzx/t17Crf0T/2+8+reo+MU39lqCr02sAkcC1k/LzyBvSDEtu9N/9NHicr jA3SvDqg5s44DFlaNZ/8BW37fGEf2rk13S/q68OVVyzac7IT7yE7PIL9XZ/6LsmrY
3mh7Y/nZm52hyLa37978f+PyOCqUh0Wfx2PL3vglofi0l
QVrOM1pg+mFLEIC88B706UzL4Pss7ouEo+EsrES+/qJq9Y1e/UGvwefOWSL2TJdt
man grep
Read up about the difference between between regular and extended patterns. You need the -E option.
Is there a way to grep (or use another command) to find exact strings, using NO regex?
For example, if I want to search for (literally):
/some/file"that/has'lots\of"invalid"chars/and.triggers$(#2)[*~.old][3].html
I don't want to go through and escape every single "escapable". Essentially, I want to pass it through, like I would with echo:
$ echo "/some/file\"that/has'lots\of\"invalid\"chars/and.triggers$(#2)[*~.old][3].html"
/some/file"that/has'lots\of"invalid"chars/and.triggers$(#2)[*~.old][3].html
Use fgrep, it's the same as grep -F (matches a fixed string).
Well, you can put the information you want to match, each in a line, and then use grep:
grep -F -f patterns.txt file.txt
Notice the usage of the flag -F, which causes grep to consider each line of the file patterns.txt as a fixed-string to be searched in file.txt.