All Questions
17
questions
1
vote
1
answer
2k
views
grep: use square brackets to match specific characters
So I am experimenting with the power of grep using this resources
The problem I am currently encountering is that it doesn't seem to work as I intended. so I have an demo.txt file that contains foo....
- 181
5
votes
2
answers
26k
views
How do I grep multiple patterns from a pipe
I want to find three patterns in a list. I tried typing
$ pip3 list | grep -ei foo -ei bar -ei baz
but the shell throws a broken pipe error and a large Traceback.
How do I grep for multiple ...
- 1,116
4
votes
3
answers
15k
views
How can search for both single quotes and double quotes in a grep search?
When I do a search bindkey in the zsh plugins directory for key conflicts I get responses from both the .zsh script files and .md files, and some of the zsh readme files use a double quote in the ...
- 7,619
10
votes
3
answers
17k
views
shell test whether multiple lines string contains specified pattern in last line
I want to determine whether a multi-line string ends with a line containing specified pattern.
These code failed, it doesn't match.
s=`echo hello && echo world && echo OK`
[[ "$s" =~ ...
- 325
9
votes
1
answer
1k
views
Why does `grep fil*` fail?
I found echo file|grep fil* fails, but echo abcd|grep abc* succeeds.
I don't understand it, can someone explain?
- 783
3
votes
2
answers
4k
views
Define a variable to awk pattern matching from bash
I am trying to grab 100 lines after the text "time: X" with X in {0,40,80,...,200}. Here is what I have so far:
#!/bin/bash
start=1
end=5
for i in $(seq $start $end);do
j=$(($i*40))
awk '/time: ...
- 31
1
vote
2
answers
2k
views
How to search parenthesis by ack
I want to search for a parentheis ( using ack, but neither using ( nor \( worked.
The first one ("(") is recognized as a multiple line command.
The second one ("\(") is treated as an invalid regular ...
- 5,265
10
votes
4
answers
6k
views
Regular expression using \\ vs using \
Why does
grep e\\.g\\. <<< "this is an e.g. wow"
and
grep e\.g\. <<< "this is an e.g. wow"
do the same thing?
If I add a third slash, it also has the same result. BUT, once I ...
- 101
5
votes
1
answer
7k
views
command: ls /etc | sort | grep d* is yielding no results but ls /etc | sort | grep p* lists entire directory
I am playing around with piping and grep tonight. I know that grep uses regex and that * means 0 or more occurrences of the preceding character. So the way I understand it is that if I do the ...
- 51
8
votes
5
answers
15k
views
bash event not found trying to match and exclude parenthesis in grep
In a very long line I'll summarize with:
(foo),(bar,baz(word,right),(end)
I want to print only:
(bar,baz(word,right
To match the second parenthesis, I exclude the word that follows the third ...
- 1,969
2
votes
2
answers
1k
views
What does this regex mean?
I was working on the conversion of Unix newline to Windows newline. I tried to unix2dos but it gave me some binary error, so I looked it up and stumbled upon this regex
sed 's/$'"/`echo \\\r`/" input....
- 705
8
votes
3
answers
33k
views
Escaping * with Regular Expressions and Grep
I have a file that has unique lines that start with 2 stars (**).
However when I run a grep command for
grep \*\* fileName
I get all of the lines in the file. This is very unusual, and what I see ...
- 743
3
votes
1
answer
192
views
find utility does not recognize bracket notation
I've two files in the current folder:
submitWeb.m
submit.m
the following find does not show the two files:
find . -regex .*submit\(Web\)?\.m
But the above regex expression works fine in emacs ...
- 361
1
vote
2
answers
3k
views
Weird zsh grep -P behaviour
I connect to server with PuTTY from Windows.
I have a long yet not touched (I suppose) by hands of local admin config:
$ cat /opt/jira/.subversion/config
...
### must be enabled, which is ...
- 144
806
votes
13
answers
1.8m
views
How do I grep for multiple patterns with pattern having a pipe character?
I want to find all lines in several files that match one of two patterns. I tried to find the patterns I'm looking for by typing
grep (foo|bar) *.txt
but the shell interprets the | as a pipe and ...
- 9,532