I want to find files that have "abc" AND "efg" in that order, and those two strings are on different lines in that file. Eg: a file with content:
blah blah..
blah blah..
blah abc blah
blah blah..
blah blah..
blah blah..
blah efg blah blah
blah blah..
blah blah..
Should be matched.
Grep is an awkward tool for this operation.
pcregrep which is found in most of the modern Linux systems can be used as
pcregrep -M 'abc.*(\n|.)*efg' test.txt
where -M, --multiline allow patterns to match more than one line
There is a newer pcre2grep also. Both are provided by the PCRE project.
pcre2grep is available for Mac OS X via Mac Ports as part of port pcre2:
% sudo port install pcre2
and via Homebrew as:
% brew install pcre
or for pcre2
% brew install pcre2
pcre2grep is also available on Linux (Ubuntu 18.04+)
$ sudo apt install pcre2-utils # PCRE2
$ sudo apt install pcregrep # Older PCRE
Here is a solution inspired by this answer:
if 'abc' and 'efg' can be on the same line:
grep -zl 'abc.*efg' <your list of files>
if 'abc' and 'efg' must be on different lines:
grep -Pzl '(?s)abc.*\n.*efg' <your list of files>
Params:
-P Use perl compatible regular expressions (PCRE).
-z Treat the input as a set of lines, each terminated by a zero byte instead of a newline. i.e. grep treats the input as a one big line. Note that if you don't use -l it will display matches followed by a NUL char, see comments.
-l list matching filenames only.
(?s) activate PCRE_DOTALL, which means that '.' finds any character or newline.
I'm not sure if it is possible with grep, but sed makes it very easy:
sed -e '/abc/,/efg/!d' [file-with-content]
sed should suffice as poster LJ stated above,
instead of !d you can simply use p to print:
sed -n '/abc/,/efg/p' file
I relied heavily on pcregrep, but with newer grep you do not need to install pcregrep for many of its features. Just use grep -P.
In the example of the OP's question, I think the following options work nicely, with the second best matching how I understand the question:
grep -Pzo "abc(.|\n)*efg" /tmp/tes*
grep -Pzl "abc(.|\n)*efg" /tmp/tes*
I copied the text as /tmp/test1 and deleted the 'g' and saved as /tmp/test2. Here is the output showing that the first shows the matched string and the second shows only the filename (typical -o is to show match and typical -l is to show only filename). Note that the 'z' is necessary for multiline and the '(.|\n)' means to match either 'anything other than newline' or 'newline' - i.e. anything:
user@host:~$ grep -Pzo "abc(.|\n)*efg" /tmp/tes*
/tmp/test1:abc blah
blah blah..
blah blah..
blah blah..
blah efg
user@host:~$ grep -Pzl "abc(.|\n)*efg" /tmp/tes*
/tmp/test1
To determine if your version is new enough, run man grep and see if something similar to this appears near the top:
-P, --perl-regexp
Interpret PATTERN as a Perl regular expression (PCRE, see
below). This is highly experimental and grep -P may warn of
unimplemented features.
That is from GNU grep 2.10.
This can be done easily by first using tr to replace the newlines with some other character:
tr '\n' '\a' | grep -o 'abc.*def' | tr '\a' '\n'
Here, I am using the alarm character, \a (ASCII 7) in place of a newline.
This is almost never found in your text, and grep can match it with a ., or match it specifically with \a.
If you are willing to use contexts, this could be achieved by typing
grep -A 500 abc test.txt | grep -B 500 efg
This will display everything between "abc" and "efg", as long as they are within 500 lines of each other.
You can do that very easily if you can use Perl.
perl -ne 'if (/abc/) { $abc = 1; next }; print "Found in $ARGV\n" if ($abc && /efg/); }' yourfilename.txt
You can do that with a single regular expression too, but that involves taking the entire contents of the file into a single string, which might end up taking up too much memory with large files. For completeness, here is that method:
perl -e '@lines = <>; $content = join("", @lines); print "Found in $ARGV\n" if ($content =~ /abc.*efg/s);' yourfilename.txt
I don't know how I would do that with grep, but I would do something like this with awk:
awk '/abc/{ln1=NR} /efg/{ln2=NR} END{if(ln1 && ln2 && ln1 < ln2){print "found"}else{print "not found"}}' foo
You need to be careful how you do this, though. Do you want the regex to match the substring or the entire word? add \w tags as appropriate. Also, while this strictly conforms to how you stated the example, it doesn't quite work when abc appears a second time after efg. If you want to handle that, add an if as appropriate in the /abc/ case etc.
Possible with ripgrep:
$ rg --multiline 'abc(\n|.)+?efg' test.txt
3:blah abc blah
4:blah abc blah
5:blah blah..
6:blah blah..
7:blah blah..
8:blah efg blah blah
Or some other incantations.
If you want . to count as a newline:
$ rg --multiline '(?s)abc.+?efg' test.txt
3:blah abc blah
4:blah abc blah
5:blah blah..
6:blah blah..
7:blah blah..
8:blah efg blah blah
Or equivalent to having the (?s) would be rg --multiline --multiline-dotall
And to answer the original question, where they have to be on separate lines:
$ rg --multiline 'abc.*[\n](\n|.)*efg' test.txt
And if you want it "non greedy" so you don't just get the first abc with the last efg (separate them into pairs):
$ rg --multiline 'abc.*[\n](\n|.)*?efg' test.txt
https://til.hashrocket.com/posts/9zneks2cbv-multiline-matches-with-ripgrep-rg
I released a grep alternative a few days ago that does support this directly, either via multiline matching or using conditions - hopefully it is useful for some people searching here. This is what the commands for the example would look like:
Multiline:
sift -lm 'abc.*efg' testfile
Conditions:
sift -l 'abc' testfile --followed-by 'efg'
You could also specify that 'efg' has to follow 'abc' within a certain number of lines:
sift -l 'abc' testfile --followed-within 5:'efg'
You can find more information on sift-tool.org.
If you need both words are close each other, for example no more than 3 lines, you can do this:
find . -exec grep -Hn -C 3 "abc" {} \; | grep -C 3 "efg"
Same example but filtering only *.txt files:
find . -name *.txt -exec grep -Hn -C 3 "abc" {} \; | grep -C 3 "efg"
And also you can replace grep command with egrep command if you want also find with regular expressions.
Sadly, you can't. From the grep docs:
grep searches the named input FILEs (or standard input if no files are named, or if a single hyphen-minus (-) is given as file name) for lines containing a match to the given PATTERN.
With silver searcher:
ag 'abc.*(\n|.)*efg' your_filename
similar to ring bearer's answer, but with ag instead. Speed advantages of silver searcher could possibly shine here.
While the sed option is the simplest and easiest, LJ's one-liner is sadly not the most portable. Those stuck with a version of the C Shell (instead of bash) will need to escape their bangs:
sed -e '/abc/,/efg/\!d' [file]
Which line unfortunately does not work in bash et al.
#!/bin/bash
shopt -s nullglob
for file in *
do
r=$(awk '/abc/{f=1}/efg/{g=1;exit}END{print g&&f ?1:0}' file)
if [ "$r" -eq 1 ];then
echo "Found pattern in $file"
else
echo "not found"
fi
done
I used this to extract a fasta sequence from a multi fasta file using the -P option for grep:
grep -Pzo ">tig00000034[^>]+" file.fasta > desired_sequence.fasta
The core of the regexp is the [^>] which translates to "not the greater than symbol"
If you have some estimation about the distance between the 2 strings 'abc' and 'efg' you are looking for, you might use:
grep -r . -e 'abc' -A num1 -B num2 | grep 'efg'
That way, the first grep will return the line with the 'abc' plus #num1 lines after it, and #num2 lines after it, and the second grep will sift through all of those to get the 'efg'. Then you'll know at which files they appear together.
With ugrep released a few months ago:
ugrep 'abc(\n|.)+?efg'
This tool is highly optimized for speed. It's also GNU/BSD/PCRE-grep compatible.
Note that we should use a lazy repetition +?, unless you want to match all lines with efg together until the last efg in the file.
You have at least a couple options --
example-text:
true
match me
false
match me one
false
match me two
true
match me three
third line!!
{BLANK_LINE}
command:
grep -Pozi '(?s)true.+?\n(?=\n)' example-text
-p for perl regular expressions
-o to only match pattern, not whole line
-z to allow line breaks
-i makes case-insensitive
output:
true
match me
true
match me three
third line!!
notes:
- +? makes modifier non-greedy so matches shortest string instead of largest (prevents from returning one match containing entire text)
command:
grep -Pozi 'true(.|\n)+?\n(?=\n)'
output:
true
match me
true
match me three
third line!!
you can use grep incase you are not keen in the sequence of the pattern.
grep -l "pattern1" filepattern*.* | xargs grep "pattern2"
example
grep -l "vector" *.cpp | xargs grep "map"
grep -l will find all the files which matches the first pattern, and xargs will grep for the second pattern. Hope this helps.
As an alternative to Balu Mohan's answer, it is possible to enforce the order of the patterns using only grep, head and tail:
for f in FILEGLOB; do tail $f -n +$(grep -n "pattern1" $f | head -n1 | cut -d : -f 1) 2>/dev/null | grep "pattern2" &>/dev/null && echo $f; done
This one isn't very pretty, though. Formatted more readably:
for f in FILEGLOB; do
tail $f -n +$(grep -n "pattern1" $f | head -n1 | cut -d : -f 1) 2>/dev/null \
| grep -q "pattern2" \
&& echo $f
done
This will print the names of all files where "pattern2" appears after "pattern1", or where both appear on the same line:
$ echo "abc
def" > a.txt
$ echo "def
abc" > b.txt
$ echo "abcdef" > c.txt; echo "defabc" > d.txt
$ for f in *.txt; do tail $f -n +$(grep -n "abc" $f | head -n1 | cut -d : -f 1) 2>/dev/null | grep -q "def" && echo $f; done
a.txt
c.txt
d.txt
tail -n +i - print all lines after the ith, inclusivegrep -n - prepend matching lines with their line numbershead -n1 - print only the first rowcut -d : -f 1 - print the first cut column using : as the delimiter2>/dev/null - silence tail error output that occurs if the $() expression returns emptygrep -q - silence grep and return immediately if a match is found, since we are only interested in the exit code
The filepattern *.sh is important to prevent directories to be inspected. Of course some test could prevent that too.
for f in *.sh
do
a=$( grep -n -m1 abc $f )
test -n "${a}" && z=$( grep -n efg $f | tail -n 1) || continue
(( ((${z/:*/}-${a/:*/})) > 0 )) && echo $f
done
The
grep -n -m1 abc $f
searches maximum 1 matching and returns (-n) the linenumber. If a match was found (test -n ...) find the last match of efg (find all and take the last with tail -n 1).
z=$( grep -n efg $f | tail -n 1)
else continue.
Since the result is something like 18:foofile.sh String alf="abc"; we need to cut away from ":" till end of line.
((${z/:*/}-${a/:*/}))
Should return a positive result if the last match of the 2nd expression is past the first match of the first.
Then we report the filename echo $f.
Here's a way by using two greps in a row:
egrep -o 'abc|efg' $file | grep -A1 abc | grep efg | wc -l
returns 0 or a positive integer.
egrep -o (Only shows matches, trick: multiple matches on the same line produce multi-line output as if they are on different lines)
grep -A1 abc (print abc and the line after it)
grep efg | wc -l (0-n count of efg lines found after abc on the same or following lines, result can be used in an 'if")
grep can be changed to egrep etc. if pattern matching is needed
To search recursively across all files (across multiple lines within each file) with BOTH strings present (i.e. string1 and string2 on different lines and both present in same file):
grep -r -l 'string1' * > tmp; while read p; do grep -l 'string2' $p; done < tmp; rm tmp
To search recursively across all files (across multiple lines within each file) with EITHER string present (i.e. string1 and string2 on different lines and either present in same file):
grep -r -l 'string1\|string2' *
I believe the following should work and has the advantage of only using extended regular expressions without the need to install an extra tool like pcregrep if you don’t have it yet or don’t have the -P option to grep available (eg. macOS):
egrep -irzo “.*abc(.*\s.*){1,}.*efg.*" path_to_filenames
Caveat emptor: this does some slight disadvantages:
abc to the last efg in each file, unless...abc [stuff] efg pattern in each file.
Using any awk and only reading 1 line at a time into memory:
$ awk 'f && /efg/{print FILENAME; exit} /abc/{f=1}' file
file
Obviously you could change it to print whatever you like, I'm just guessing you want the name of the file printed.
If you want a succ/fail exit status like you'd get from grep then tweak it to:
awk 'f && /efg/{f++; exit} /abc/{f=1} END{ if (f==2) { print FILENAME; exit 0 } else exit 1 }' file
or if you want to handle multiple input files and your awk supports nextfile:
awk 'FNR==1{f=0} f && /efg/{print FILENAME; nextfile} /abc/{f=1}' file1 file2 ...
etc...
This should work:
cat FILE | egrep 'abc|efg'
If there is more than one match you can filter out using grep -v
