I would like to search from the first output of grep. First grep I search all the files from yesterday that has the word "abc". I would like to also find if it has "def" from first search.
This is what I have
find /tttt/aaaa/bbb -type f -mtime -1 -mtime 0 -print0| xargs -0 grep -l "abc"
I would like to find the output that also contains "def".
It sounds like you are wanting to search for multiple strings in a list. This can be accomplished with the -E switch on grep. This allows you to provide search strings separated with a pipe.
grep -E 'abc|def'
Another option is to use a backslash on the pipe:
grep 'abc\|def'
EDIT: Oops. I thought you wanted an OR, but you want an AND.
You just need to add another pipe to grep at the end of your one-liner:
| xargs grep -l 'def'
Related
In the Unix command line (CentOS7) I have to use the grep command to find all words with:
At least n characters
At most n characters
Exactly n characters
I have searched the posts here for answers and came up with grep -E '^.{8}' /sample/dir but this only gets me the words with at least 8 characters.
Using the $ at the end returns nothing. For example:
grep -E '^.{8}$' /sample/dir
I would also like to trim the info in /sample/dir so that I only see the specific information. I tried using a pipe:
cut -f1,7 -d: | grep -E '^.{8}' /sample/dir
Depending on the order, this only gets me one or the other, not both.
I only want the usernames at the beginning of each line, not all words in each line for the entire file.
For example, if I want to find userids on my system, these should be the results:
1.
tano-ahsoka
skywalker-a
kenobi-obiwan
ahsoka-t
luke-s
leia-s
ahsoka-t
kenobi-o
grievous
I'm looking for two responses here as I have already figured out number 1.
Numbers 2 and 3 are not working for some reason.
If possible, I'd also like to apply the cut for all three outputs.
Any and all help is appreciated, thank you!
You can run one grep for extracting the words, and another for filtering based on length.
grep -oE '(\w|-)+' file | grep -Ee '^.{8,}$'
grep -oE '(\w|-)+' file | grep -Ee '^.{,8}$'
grep -oE '(\w|-)+' file | grep -Ee '^.{8}$'
Update the pattern based on requirements and maybe use -r and specify a directory instead of a file. Adding -h option may also be needed to prevent the filenames from being printed.
Depending on your implementation of grep, it might work to use:
grep -o -E '\<\w{8}\>' # exactly 8
grep -o -E '\<\w{8,}\>' # 8 or more
grep -o -E '\<\w{,8}\>' # 8 or less
Let's say I have queries.txt.
queries.txt:
cat
dog
123
now I want to use them are queries to find lines in myDocument.txt using grep.
cat queries.txt | xargs grep -f myDocument.txt
myDocument has lines like
cat
i have a dog
123
mouse
it should return the first 3 lines. but it's not. instead, grep tries to find them as file names. what am i doing wrong?
Here, you just need:
grep -f queries.txt myDocument.txt
This causes grep to read the regular expressions from the file queries.txt and then apply them to myDocument.txt.
In the xargs version, you were effectively writing:
grep -f myDocument.txt cat dog 123
If you absolutely must use xargs, then you'll need to write:
xargs -I % grep -e % myDocument.txt < queries.txt
This avoids a UUOC — Useless Use of cat – award by redirecting standard input from queries.txt. It uses the -I % option to specify where the replacement text should go in the command line. Using the -e option means that if the pattern is, say --help, you won't run into problems with (GNU) grep treating that as an argument (and therefore printing its help message).
The grep -e option will take a pattern string as an argument. -f treats the argument as a file name of a file with patterns in it.
This question already has answers here:
How to pass command output as multiple arguments to another command
(5 answers)
Read expression for grep from standard input
(1 answer)
Closed last month.
I am looking for insight as to how pipes can be used to pass standard output as the arguments for other commands.
For example, consider this case:
ls | grep Hello
The structure of grep follows the pattern: grep SearchTerm PathOfFileToBeSearched. In the case I have illustrated, the word Hello is taken as the SearchTerm and the result of ls is used as the file to be searched. But what if I want to switch it around? What if I want the standard output of ls to be the SearchTerm, with the argument following grep being PathOfFileToBeSearched? In a general sense, I want to have control over which argument the pipe fills with the standard output of the previous command. Is this possible, or does it depend on how the script for the command (e.g., grep) was written?
Thank you so much for your help!
grep itself will be built such that if you've not specified a file name, it will open stdin (and thus get the output of ls). There's no real generic mechanism here - merely convention.
If you want the output of ls to be the search term, you can do this via the shell. Make use of a subshell and substitution thus:
$ grep $(ls) filename.txt
In this scenario ls is run in a subshell, and its stdout is captured and inserted in the command line as an argument for grep. Note that if the ls output contains spaces, this will cause confusion for grep.
There are basically two options for this: shell command substitution and xargs. Brian Agnew has just written about the former. xargs is a utility which takes its stdin and turns it into arguments of a command to execute. So you could run
ls | xargs -n1 -J % grep -- % PathOfFileToBeSearched
and it would, for each file output by ls, run grep -e filename PathOfFileToBeSearched to grep for the filename output by ls within the other file you specify. This is an unusual xargs invocation; usually it's used to add one or more arguments at the end of a command, while here it should add exactly one argument in a specific place, so I've used -n and -J arguments to arrange that. The more common usage would be something like
ls | xargs grep -- term
to search all of the files output by ls for term. Although of course if you just want files in the current directory, you can this more simply without a pipeline:
grep -- term *
and likewise in your reversed arrangement,
for filename in *; do
grep -- "$#" PathOfFileToBeSearched
done
There's one important xargs caveat: whitespace characters in the filenames generated by ls won't be handled too well. To do that, provided you have GNU utilities, you can use find instead.
find . -mindepth 1 -maxdepth 1 -print0 | xargs -0 -n1 -J % grep -- % PathOfFileToBeSearched
to use NUL characters to separate filenames instead of whitespace
Unfortunately, due to the limitations of our Unix Tru64 environment, I am unable to use the GREP -r switch to perform my search for strings within files across multiple directories and sub directories.
Ideally, I would like to pass two parameters. The first will be the directory I want my search is to start on. The second is a file containing a list of all the strings to be searched. This list will consist of various directory path names and will include special characters:
ie:
/aaa/bbb/ccc
/eee/dddd/ggggggg/
etc..
The purpose of this exercise is to identify all shell scripts that may have specific hard coded path names identified in my list.
There was one example I found during my investigations that perhaps comes close, but I am not sure how to customize this to accept a file of string arguments:
eg: find etb -exec grep test {} \;
where 'etb' is the directory and 'test', a hard coded string to be searched.
This should do it:
find dir -type f -exec grep -F -f strings.txt {} \;
dir is the directory from which searching will commence
strings.txt is the file of strings to match, one per line
-F means treat search strings as literal rather than regular expressions
-f strings.txt means use the strings in strings.txt for matching
You can add -l to the grep switches if you just want filenames that match.
Footnote:
Some people prefer a solution involving xargs, e.g.
find dir -type f -print0 | xargs -0 grep -F -f strings.txt
which is perhaps a little more robust/efficient in some cases.
By reading, I assume we can not use the gnu coreutil, and egrep is not available.
I assume (for some reason) the system is broken, and escapes do not work as expected.
Under normal situations, grep -rf patternfile.txt /some/dir/ is the way to go.
a file containing a list of all the strings to be searched
Assumptions : gnu coreutil not available. grep -r does not work. handling of special character is broken.
Now, you have working awk ? no ?. It makes life so much easier. But lets be on the safe side.
Assume : working sed ,one of od OR hexdump OR xxd (from vim package) is available.
Lets call this patternfile.txt
1. Convert list into a regexp that grep likes
Example patternfile.txt contains
/foo/
/bar/doe/
/root/
(example does not print special char, but it's there.) we must turn it into something like
(/foo/|/bar/doe/|/root/)
Assuming echo -en command is not broken, and xxd , or od, or hexdump is available,
Using hexdump
cat patternfile.txt |hexdump -ve '1/1 "%02x \n"' |tr -d '\n'
Using od
cat patternfile.txt |od -A none -t x1|tr -d '\n'
and pipe it into (common for both hexdump and od)
|sed 's:[ ]*0a[ ]*$::g'|sed 's: 0a:\\|:g' |sed 's:^[ ]*::g'|sed 's:^: :g' |sed 's: :\\x:g'
then pipe result into
|sed 's:^:\\(:g' |sed 's:$:\\):g'
and you have a regexp pattern that is escaped.
2. Feed the escaped pattern into broken regexp
Assuming the bare minimum shell escape is available,
we use grep "$(echo -en "ESCAPED_PATTERN" )" to do our job.
3. To sum it up
Building a escaped regexp pattern (using hexdump as example )
grep "$(echo -en "$( cat patternfile.txt |hexdump -ve '1/1 "%02x \n"' |tr -d '\n' |sed 's:[ ]*0a[ ]*$::g'|sed 's: 0a:\\|:g' |sed 's:^[ ]*::g'|sed 's:^: :g' |sed 's: :\\x:g'|sed 's:^:\\(:g' |sed 's:$:\\):g')")"
will escape all characters and enclose it with (|) brackets so a regexp OR match will be performed.
4. Recrusive directory lookup
Under normal situations, even when grep -r is broken, find /dir/ -exec grep {} \; should work.
Some may prefer xargs instaed (unless you happen to have buggy xargs).
We prefer find /somedir/ -type f -print0 |xargs -0 grep -f 'patternfile.txt' approach, but since
this is not available (for whatever valid reason),
we need to exec grep for each file,and this is normaly the wrong way.
But lets do it.
Assume : find -type f works.
Assume : xargs is broken OR not available.
First, if you have a buggy pipe, it might not handle large number of files.
So we avoid xargs in such systems (i know, i know, just lets pretend it is broken ).
find /whatever/dir/to/start/looking/ -type f > list-of-all-file-to-search-for.txt
IF your shell handles large size lists nicely,
for file in cat list-of-all-file-to-search-for.txt ; do grep REGEXP_PATTERN "$file" ;
done ; is a nice way to get by. Unfortunetly, some systems do not like that,
and in that case, you may require
cat list-of-all-file-to-search-for.txt | split --help -a 4 -d -l 2000 file-smaller-chunk.part.
to turn it into smaller chunks. Now this is for a seriously broken system.
then a for file in file-smaller-chunk.part.* ; do for single_line in cat "$file" ; do grep REGEXP_PATTERN "$single_line" ; done ; done ;
should work.
A
cat filelist.txt |while read file ; do grep REGEXP_PATTERN $file ; done ;
may be used as workaround on some systems.
What if my shell doe not handle quotes ?
You may have to escape the file list beforehand.
It can be done much nicer in awk, perl, whatever, but since we restrict our selves to
sed, lets do it.
We assume 0x27, the ' code will actually work.
cat list-of-all-file-to-search-for.txt |sed 's#['\'']#'\''\\'\'\''#g'|sed 's:^:'\'':g'|sed 's:$:'\'':g'
The only time I had to use this was when feeding output into bash again.
What if my shell does not handle that ?
xargs fails , grep -r fails , shell's for loop fails.
Do we have other things ? YES.
Escape all input suitable for your shell, and make a script.
But you know what, I got board, and writing automated scripts for csh just seems
wrong. So I am going to stop here.
Take home note
Use the tool for the right job. Writing a interpreter on bc is perfectly
capable, but it is just plain wrong. Install coreutils, perl, a better grep
what ever. makes life a better thing.
I am using the following command to grep stuff in subdirs
find . | xargs grep -s 's:text'
However, this also finds stuff like <s:textfield name="sdfsf"...../>
What can I do to avoid that so it just finds stuff like <s:text name="sdfsdf"/>
OR for that matter....also finds <s:text somethingElse="lkjkj" name="lkkj"
basically s:text and name should be on same line....
You want the -w option to specify that it's the end of a word.
find . | xargs grep -sw 's:text'
Use \b to match on "word boundaries", which will make your search match on whole words only.
So your grep would look something like
grep -r "\bSTRING\b"
adding color and line numbers might help too
grep --color -rn "\bSTRING\b"
From http://www.regular-expressions.info/wordboundaries.html:
There are three different positions that qualify as word boundaries:
Before the first character in the string, if the first character is a
word character.
After the last character in the string, if the last
character is a word character.
Between two characters in the string,
where one is a word character and the other is not a word character.
You can drop the xargs command by making grep search recursively. And you normally don't need the 's' flag. Hence:
grep -wr 's:text'
you could try rg, https://github.com/BurntSushi/ripgrep :
rg -w 's:text' .
should do it
Use -w option for whole word match. Sample given below:
[binita#ubuntu ~]# a="abcd efg"
[binita#ubuntu ~]# echo $a
abcd efg
[binita#ubuntu ~]# echo $a | grep ab
abcd efg
[binita#ubuntu ~]# echo $a | grep -w ab
[binita#ubuntu ~]# echo $a | grep -w abcd
abcd efg
This is another way of setting the boundaries of the word, note that it doesn't work without the quotes around it:
grep -r '\<s:text\>' .
If you just want to filter out the remainder text part, you can do this.
xargs grep -s 's:text '
This should find only s:text instances with a space after the last t. If you need to find s:text instances that only have a name element, either pipe your results to another grep expression, or use regex to filter only the elements you need.