Write output out of grep into a file on Linux? - linux

find . -name "*.php" | xargs grep -i -n "searchstring" >output.txt
Here I am trying to write data into a file which is not happening...

How about appending results using >>?
find . -name "*.php" | xargs grep -i -n "searchstring" >> output.txt
I haven't got a Linux box with me right now, so I'll try to improvize.
the xargs grep -i -n "searchstring" bothers me a bit.
Perhaps you meant xargs -I {} grep -i "searchstring" {}, or just xargs grep -i "searchstring"?
Since -n as grep's argument will give you only number lines, I doubt this is what you needed.
This way, your final code would be
find . -name "*.php" | xargs grep -i "searchstring" >> output.txt

find . -name "*.php" -exec grep -i -n "function" {} \; >output.txt
But you won't know what file it came from. You might want:
find . -name "*.php" -exec grep -i -Hn "function" {} \; >output.txt
instead.

I guess that you have spaces in the php filenames. If you hand them to grep through xargs in the way that you do, the names get split into parts and grep interprets those parts as filenames which it then cannot find.
There is a solution for that. find has a -print0 option that instructs find to separate results by a NUL byte and xargs has a -0 option that instructs xargs to expect a NUL byte as separator. Using those you get:
find . -name "*.php" -print0 | xargs -0 grep -i -n "searchstring" > output.txt

Try using line-buffered
grep --line-buffered
[edit]
I ran your original command on my box and it seems to work fine, so I'm not sure anymore.

Looks fine to me. What happens if you remove >output.txt?

If you're searching trees of source code, please consider using ack. To do what you're doing in ack, regardless of there being spaces in filenames, you'd do:
ack --php -i searchstring > output.txt

I always use the following command. It displays the output on a console and also creates the file
grep -r "string to be searched" . 2>&1 | tee /your/path/to/file/filename.txt

Check free disk space by
$ df -Th
It could be not enough free space on your disk.

Related

Why does Perl delete file content when used with find?

Can anyone see why Perl deletes all file content when it is used together with find?
echo stning >> test.tex
echo stning >> test.tex
find . -type f -name \*.tex -print0 | xargs -0 perl -i -ne 's/stning/sætning/g'
cat test.tex
The last command doesn't return anything, and that the issue.
You need -p, not -n. The -n flag only reads, but doesn't print.
find . -type f -name \*.tex -print0 | xargs -0 perl -i -pe 's/stning/sætning/g'
You can easily remember this with the mnemonic perl pie, which is perl -p -i -e or shorter perl -pi -e.
You can achieve your result with sed itself. As just you need an inline replacement.
find . -type f -name \*.tex -print0 | xargs -0 sed -i 's/stning/sætning/g'

how do I change string in all sub directories with same file name (For eg: data.txt) in linux using termianl?

find . -name "data.txt" -print0 | grep -rl "pa028" ./ |xargs -0 sed -i '' -e 's/pa028/pa014/g'
I tried to replace pa028 with pa014 in the file name "data.txt" in all subdirectories. Can you find please correct me?
You can't put grep between find -print0 and xargs -0 because grep operates on lines, and this pipeline contains null-separated text instead of lines. Additionally, grep -r . will ignore the standard input you so expensively set up find to produce.
find . -name "data.txt" -exec grep -q "pa028" {} \; -print0 |
xargs -r -0 sed -i '' -e 's/pa028/pa014/g'
The logic here is to use -exec grep -q as a predicate to find so we produce a null-terminated list of matching files (for which the -exec returns true) to pass to xargs -r -0. (The -r option is important, too; you get weird errors if xargs runs anyway even though find produced no output.)
There is an extension to GNU grep to operate on null-terminated strings with -z and print null-terminated file names with -Z -l but that's a fairly recent development, so I'm not yet prepared to recommend that.

Grep - How to concatenate filename to each returned line of file content?

I have a statement which
Finds a set of files
Cats their contents out
Then greps their contents
It is this pipeline:
find . | grep -i "Test_" | xargs cat | grep -i "start-node name="
produces an output such as:
<start-node name="Start" secure="false"/>
<start-node name="Run" secure="false"/>
What I was hoping to get is something like:
filename1-<start-node name="Start" secure="false"/>
filename2-<start-node name="Run" secure="false"/>
An easier may be to execute grep on the result of find, without xargs and cat:
grep -i "Test_" `find .` | grep -i "start-node name="
Because you cat all the files into a single stream, grep doesn't have any filename information. You want to give all the filenames to grep as arguments:
find ... | xargs grep "<start-node name=" /dev/null
Note two additional changes - I've dropped the -i flag, as it appears you're inspecting XML, and that's not case-insensitive; I've added /dev/null to the list of files, so that grep always has at least two files of input, even if find only gives one result. That's the portable way to get grep to print filenames.
Now, let's look at the find command. Instead of finding all files, then filtering through grep, we can use the -iregex predicate of GNU grep:
find . -iregex '.*Test_.*' \( -type 'f' -o -type 'l' \) | xargs grep ...
The mixed-case pattern suggests your filenames aren't really case-insensitive, and you might not want to grep symlinks (I'm sure you don't want directories and special files passed through), in which case you can simplify (and can use portable find again):
find . -name '*Test_*' -type 'f' | xargs grep ...
Now protect against the kind of filenames that trip up pipelines, and you have
find . -name '*Test_*' -type 'f' -print0 \
| xargs -0 grep -e "<start-node name=" -- /dev/null
Alternatively, if you have GNU grep, you don't need find at all:
grep --recursive --include '*[Tt]est_*' -e "<start-node name=" .
If you just need to count them:
find . | grep -i "Test_" | xargs cat | grep -i "start-node name=" | awk 'BEGIN{n=0}{n=n+1;print "filename" n "-" $0}'
From man grep:
-H Always print filename headers with output lines.

Bash script to recursively find and replace in files [duplicate]

How do I find and replace every occurrence of:
subdomainA.example.com
with
subdomainB.example.com
in every text file under the /home/www/ directory tree recursively?
find /home/www \( -type d -name .git -prune \) -o -type f -print0 | xargs -0 sed -i 's/subdomainA\.example\.com/subdomainB.example.com/g'
-print0 tells find to print each of the results separated by a null character, rather than a new line. In the unlikely event that your directory has files with newlines in the names, this still lets xargs work on the correct filenames.
\( -type d -name .git -prune \) is an expression which completely skips over all directories named .git. You could easily expand it, if you use SVN or have other folders you want to preserve -- just match against more names. It's roughly equivalent to -not -path .git, but more efficient, because rather than checking every file in the directory, it skips it entirely. The -o after it is required because of how -prune actually works.
For more information, see man find.
The simplest way for me is
grep -rl oldtext . | xargs sed -i 's/oldtext/newtext/g'
Note: Do not run this command on a folder including a git repo - changes to .git could corrupt your git index.
find /home/www/ -type f -exec \
sed -i 's/subdomainA\.example\.com/subdomainB.example.com/g' {} +
Compared to other answers here, this is simpler than most and uses sed instead of perl, which is what the original question asked for.
All the tricks are almost the same, but I like this one:
find <mydir> -type f -exec sed -i 's/<string1>/<string2>/g' {} +
find <mydir>: look up in the directory.
-type f:
File is of type: regular file
-exec command {} +:
This variant of the -exec action runs the specified command on the selected files, but the command line is built by appending
each selected file name at the end; the total number of invocations of the command will be much less than the number of
matched files. The command line is built in much the same way that xargs builds its command lines. Only one instance of
`{}' is allowed within the command. The command is executed in the starting directory.
For me the easiest solution to remember is https://stackoverflow.com/a/2113224/565525, i.e.:
sed -i '' -e 's/subdomainA/subdomainB/g' $(find /home/www/ -type f)
NOTE: -i '' solves OSX problem sed: 1: "...": invalid command code .
NOTE: If there are too many files to process you'll get Argument list too long. The workaround - use find -exec or xargs solution described above.
cd /home/www && find . -type f -print0 |
xargs -0 perl -i.bak -pe 's/subdomainA\.example\.com/subdomainB.example.com/g'
For anyone using silver searcher (ag)
ag SearchString -l0 | xargs -0 sed -i 's/SearchString/Replacement/g'
Since ag ignores git/hg/svn file/folders by default, this is safe to run inside a repository.
This one is compatible with git repositories, and a bit simpler:
Linux:
git grep -l 'original_text' | xargs sed -i 's/original_text/new_text/g'
Mac:
git grep -l 'original_text' | xargs sed -i '' -e 's/original_text/new_text/g'
(Thanks to http://blog.jasonmeridth.com/posts/use-git-grep-to-replace-strings-in-files-in-your-git-repository/)
To cut down on files to recursively sed through, you could grep for your string instance:
grep -rl <oldstring> /path/to/folder | xargs sed -i s^<oldstring>^<newstring>^g
If you run man grep you'll notice you can also define an --exlude-dir="*.git" flag if you want to omit searching through .git directories, avoiding git index issues as others have politely pointed out.
Leading you to:
grep -rl --exclude-dir="*.git" <oldstring> /path/to/folder | xargs sed -i s^<oldstring>^<newstring>^g
A straight forward method if you need to exclude directories (--exclude-dir=..folder) and also might have file names with spaces (solved by using 0Byte for both grep -Z and xargs -0)
grep -rlZ oldtext . --exclude-dir=.folder | xargs -0 sed -i 's/oldtext/newtext/g'
An one nice oneliner as an extra. Using git grep.
git grep -lz 'subdomainA.example.com' | xargs -0 perl -i'' -pE "s/subdomainA.example.com/subdomainB.example.com/g"
Simplest way to replace (all files, directory, recursive)
find . -type f -not -path '*/\.*' -exec sed -i 's/foo/bar/g' {} +
Note: Sometimes you might need to ignore some hidden files i.e. .git, you can use above command.
If you want to include hidden files use,
find . -type f -exec sed -i 's/foo/bar/g' {} +
In both case the string foo will be replaced with new string bar
find /home/www/ -type f -exec perl -i.bak -pe 's/subdomainA\.example\.com/subdomainB.example.com/g' {} +
find /home/www/ -type f will list all files in /home/www/ (and its subdirectories).
The "-exec" flag tells find to run the following command on each file found.
perl -i.bak -pe 's/subdomainA\.example\.com/subdomainB.example.com/g' {} +
is the command run on the files (many at a time). The {} gets replaced by file names.
The + at the end of the command tells find to build one command for many filenames.
Per the find man page:
"The command line is built in much the same way that
xargs builds its command lines."
Thus it's possible to achieve your goal (and handle filenames containing spaces) without using xargs -0, or -print0.
I just needed this and was not happy with the speed of the available examples. So I came up with my own:
cd /var/www && ack-grep -l --print0 subdomainA.example.com | xargs -0 perl -i.bak -pe 's/subdomainA\.example\.com/subdomainB.example.com/g'
Ack-grep is very efficient on finding relevant files. This command replaced ~145 000 files with a breeze whereas others took so long I couldn't wait until they finish.
or use the blazing fast GNU Parallel:
grep -rl oldtext . | parallel sed -i 's/oldtext/newtext/g' {}
grep -lr 'subdomainA.example.com' | while read file; do sed -i "s/subdomainA.example.com/subdomainB.example.com/g" "$file"; done
I guess most people don't know that they can pipe something into a "while read file" and it avoids those nasty -print0 args, while presevering spaces in filenames.
Further adding an echo before the sed allows you to see what files will change before actually doing it.
Try this:
sed -i 's/subdomainA/subdomainB/g' `grep -ril 'subdomainA' *`
According to this blog post:
find . -type f | xargs perl -pi -e 's/oldtext/newtext/g;'
#!/usr/local/bin/bash -x
find * /home/www -type f | while read files
do
sedtest=$(sed -n '/^/,/$/p' "${files}" | sed -n '/subdomainA/p')
if [ "${sedtest}" ]
then
sed s'/subdomainA/subdomainB/'g "${files}" > "${files}".tmp
mv "${files}".tmp "${files}"
fi
done
If you do not mind using vim together with grep or find tools, you could follow up the answer given by user Gert in this link --> How to do a text replacement in a big folder hierarchy?.
Here's the deal:
recursively grep for the string that you want to replace in a certain path, and take only the complete path of the matching file. (that would be the $(grep 'string' 'pathname' -Rl).
(optional) if you want to make a pre-backup of those files on centralized directory maybe you can use this also: cp -iv $(grep 'string' 'pathname' -Rl) 'centralized-directory-pathname'
after that you can edit/replace at will in vim following a scheme similar to the one provided on the link given:
:bufdo %s#string#replacement#gc | update
You can use awk to solve this as below,
for file in `find /home/www -type f`
do
awk '{gsub(/subdomainA.example.com/,"subdomainB.example.com"); print $0;}' $file > ./tempFile && mv ./tempFile $file;
done
hope this will help you !!!
For replace all occurrences in a git repository you can use:
git ls-files -z | xargs -0 sed -i 's/subdomainA\.example\.com/subdomainB.example.com/g'
See List files in local git repo? for other options to list all files in a repository. The -z options tells git to separate the file names with a zero byte, which assures that xargs (with the option -0) can separate filenames, even if they contain spaces or whatnot.
A bit old school but this worked on OS X.
There are few trickeries:
• Will only edit files with extension .sls under the current directory
• . must be escaped to ensure sed does not evaluate them as "any character"
• , is used as the sed delimiter instead of the usual /
Also note this is to edit a Jinja template to pass a variable in the path of an import (but this is off topic).
First, verify your sed command does what you want (this will only print the changes to stdout, it will not change the files):
for file in $(find . -name *.sls -type f); do echo -e "\n$file: "; sed 's,foo\.bar,foo/bar/\"+baz+\"/,g' $file; done
Edit the sed command as needed, once you are ready to make changes:
for file in $(find . -name *.sls -type f); do echo -e "\n$file: "; sed -i '' 's,foo\.bar,foo/bar/\"+baz+\"/,g' $file; done
Note the -i '' in the sed command, I did not want to create a backup of the original files (as explained in In-place edits with sed on OS X or in Robert Lujo's comment in this page).
Happy seding folks!
just to avoid to change also
NearlysubdomainA.example.com
subdomainA.example.comp.other
but still
subdomainA.example.com.IsIt.good
(maybe not good in the idea behind domain root)
find /home/www/ -type f -exec sed -i 's/\bsubdomainA\.example\.com\b/\1subdomainB.example.com\2/g' {} \;
Here's a version that should be more general than most; it doesn't require find (using du instead), for instance. It does require xargs, which are only found in some versions of Plan 9 (like 9front).
du -a | awk -F' ' '{ print $2 }' | xargs sed -i -e 's/subdomainA\.example\.com/subdomainB.example.com/g'
If you want to add filters like file extensions use grep:
du -a | grep "\.scala$" | awk -F' ' '{ print $2 }' | xargs sed -i -e 's/subdomainA\.example\.com/subdomainB.example.com/g'
For Qshell (qsh) on IBMi, not bash as tagged by OP.
Limitations of qsh commands:
find does not have the -print0 option
xargs does not have -0 option
sed does not have -i option
Thus the solution in qsh:
PATH='your/path/here'
SEARCH=\'subdomainA.example.com\'
REPLACE=\'subdomainB.example.com\'
for file in $( find ${PATH} -P -type f ); do
TEMP_FILE=${file}.${RANDOM}.temp_file
if [ ! -e ${TEMP_FILE} ]; then
touch -C 819 ${TEMP_FILE}
sed -e 's/'$SEARCH'/'$REPLACE'/g' \
< ${file} > ${TEMP_FILE}
mv ${TEMP_FILE} ${file}
fi
done
Caveats:
Solution excludes error handling
Not Bash as tagged by OP
If you wanted to use this without completely destroying your SVN repository, you can tell 'find' to ignore all hidden files by doing:
find . \( ! -regex '.*/\..*' \) -type f -print0 | xargs -0 sed -i 's/subdomainA.example.com/subdomainB.example.com/g'
Using combination of grep and sed
for pp in $(grep -Rl looking_for_string)
do
sed -i 's/looking_for_string/something_other/g' "${pp}"
done
perl -p -i -e 's/oldthing/new_thingy/g' `grep -ril oldthing *`
to change multiple files (and saving a backup as *.bak):
perl -p -i -e "s/\|/x/g" *
will take all files in directory and replace | with x
called a “Perl pie” (easy as a pie)

Linux command: How to 'find' only text files?

After a few searches from Google, what I come up with is:
find my_folder -type f -exec grep -l "needle text" {} \; -exec file {} \; | grep text
which is very unhandy and outputs unneeded texts such as mime type information. Any better solutions? I have lots of images and other binary files in the same folder with a lot of text files that I need to search through.
I know this is an old thread, but I stumbled across it and thought I'd share my method which I have found to be a very fast way to use find to find only non-binary files:
find . -type f -exec grep -Iq . {} \; -print
The -I option to grep tells it to immediately ignore binary files and the . option along with the -q will make it immediately match text files so it goes very fast. You can change the -print to a -print0 for piping into an xargs -0 or something if you are concerned about spaces (thanks for the tip, #lucas.werkmeister!)
Also the first dot is only necessary for certain BSD versions of find such as on OS X, but it doesn't hurt anything just having it there all the time if you want to put this in an alias or something.
EDIT: As #ruslan correctly pointed out, the -and can be omitted since it is implied.
Based on this SO question :
grep -rIl "needle text" my_folder
Why is it unhandy? If you need to use it often, and don't want to type it every time just define a bash function for it:
function findTextInAsciiFiles {
# usage: findTextInAsciiFiles DIRECTORY NEEDLE_TEXT
find "$1" -type f -exec grep -l "$2" {} \; -exec file {} \; | grep text
}
put it in your .bashrc and then just run:
findTextInAsciiFiles your_folder "needle text"
whenever you want.
EDIT to reflect OP's edit:
if you want to cut out mime informations you could just add a further stage to the pipeline that filters out mime informations. This should do the trick, by taking only what comes before :: cut -d':' -f1:
function findTextInAsciiFiles {
# usage: findTextInAsciiFiles DIRECTORY NEEDLE_TEXT
find "$1" -type f -exec grep -l "$2" {} \; -exec file {} \; | grep text | cut -d ':' -f1
}
find . -type f -print0 | xargs -0 file | grep -P text | cut -d: -f1 | xargs grep -Pil "search"
This is unfortunately not space save. Putting this into bash script makes it a bit easier.
This is space safe:
#!/bin/bash
#if [ ! "$1" ] ; then
echo "Usage: $0 <search>";
exit
fi
find . -type f -print0 \
| xargs -0 file \
| grep -P text \
| cut -d: -f1 \
| xargs -i% grep -Pil "$1" "%"
Another way of doing this:
# find . |xargs file {} \; |grep "ASCII text"
If you want empty files too:
# find . |xargs file {} \; |egrep "ASCII text|empty"
How about this:
$ grep -rl "needle text" my_folder | tr '\n' '\0' | xargs -r -0 file | grep -e ':[^:]*text[^:]*$' | grep -v -e 'executable'
If you want the filenames without the file types, just add a final sed filter.
$ grep -rl "needle text" my_folder | tr '\n' '\0' | xargs -r -0 file | grep -e ':[^:]*text[^:]*$' | grep -v -e 'executable' | sed 's|:[^:]*$||'
You can filter-out unneeded file types by adding more -e 'type' options to the last grep command.
EDIT:
If your xargs version supports the -d option, the commands above become simpler:
$ grep -rl "needle text" my_folder | xargs -d '\n' -r file | grep -e ':[^:]*text[^:]*$' | grep -v -e 'executable' | sed 's|:[^:]*$||'
Here's how I've done it ...
1 . make a small script to test if a file is plain text
istext:
#!/bin/bash
[[ "$(file -bi $1)" == *"file"* ]]
2 . use find as before
find . -type f -exec istext {} \; -exec grep -nHi mystring {} \;
Here's a simplified version with extended explanation for beginners like me who are trying to learn how to put more than one command in one line.
If you were to write out the problem in steps, it would look like this:
// For every file in this directory
// Check the filetype
// If it's an ASCII file, then print out the filename
To achieve this, we can use three UNIX commands: find, file, and grep.
find will check every file in the directory.
file will give us the filetype. In our case, we're looking for a return of 'ASCII text'
grep will look for the keyword 'ASCII' in the output from file
So how can we string these together in a single line? There are multiple ways to do it, but I find that doing it in order of our pseudo-code makes the most sense (especially to a beginner like me).
find ./ -exec file {} ";" | grep 'ASCII'
Looks complicated, but not bad when we break it down:
find ./ = look through every file in this directory. The find command prints out the filename of any file that matches the 'expression', or whatever comes after the path, which in our case is the current directory or ./
The most important thing to understand is that everything after that first bit is going to be evaluated as either True or False. If True, the file name will get printed out. If not, then the command moves on.
-exec = this flag is an option within the find command that allows us to use the result of some other command as the search expression. It's like calling a function within a function.
file {} = the command being called inside of find. The file command returns a string that tells you the filetype of a file. Regularly, it would look like this: file mytextfile.txt. In our case, we want it to use whatever file is being looked at by the find command, so we put in the curly braces {} to act as an empty variable, or parameter. In other words, we're just asking for the system to output a string for every file in the directory.
";" = this is required by find and is the punctuation mark at the end of our -exec command. See the manual for 'find' for more explanation if you need it by running man find.
| grep 'ASCII' = | is a pipe. Pipe take the output of whatever is on the left and uses it as input to whatever is on the right. It takes the output of the find command (a string that is the filetype of a single file) and tests it to see if it contains the string 'ASCII'. If it does, it returns true.
NOW, the expression to the right of find ./ will return true when the grep command returns true. Voila.
I have two issues with histumness' answer:
It only list text files. It does not actually search them as
requested. To actually search, use
find . -type f -exec grep -Iq . {} \; -and -print0 | xargs -0 grep "needle text"
It spawns a grep process for every file, which is very slow. A better solution is then
find . -type f -print0 | xargs -0 grep -IZl . | xargs -0 grep "needle text"
or simply
find . -type f -print0 | xargs -0 grep -I "needle text"
This only takes 0.2s compared to 4s for solution above (2.5GB data / 7700 files), i.e. 20x faster.
Also, nobody cited ag, the Silver Searcher or ack-grep¸as alternatives. If one of these are available, they are much better alternatives:
ag -t "needle text" # Much faster than ack
ack -t "needle text" # or ack-grep
As a last note, beware of false positives (binary files taken as text files). I already had false positive using either grep/ag/ack, so better list the matched files first before editing the files.
Although it is an old question, I think this info bellow will add to the quality of the answers here.
When ignoring files with the executable bit set, I just use this command:
find . ! -perm -111
To keep it from recursively enter into other directories:
find . -maxdepth 1 ! -perm -111
No need for pipes to mix lots of commands, just the powerful plain find command.
Disclaimer: it is not exactly what OP asked, because it doesn't check if the file is binary or not. It will, for example, filter out bash script files, that are text themselves but have the executable bit set.
That said, I hope this is useful to anyone.
I do it this way:
1) since there're too many files (~30k) to search thru, I generate the text file list daily for use via crontab using below command:
find /to/src/folder -type f -exec file {} \; | grep text | cut -d: -f1 > ~/.src_list &
2) create a function in .bashrc:
findex() {
cat ~/.src_list | xargs grep "$*" 2>/dev/null
}
Then I can use below command to do the search:
findex "needle text"
HTH:)
I prefer xargs
find . -type f | xargs grep -I "needle text"
if your filenames are weird look up using the -0 options:
find . -type f -print0 | xargs -0 grep -I "needle text"
bash example to serach text "eth0" in /etc in all text/ascii files
grep eth0 $(find /etc/ -type f -exec file {} \; | egrep -i "text|ascii" | cut -d ':' -f1)
If you are interested in finding any file type by their magic bytes using the awesome file utility combined with power of find, this can come in handy:
$ # Let's make some test files
$ mkdir ASCII-finder
$ cd ASCII-finder
$ dd if=/dev/urandom of=binary.file bs=1M count=1
1+0 records in
1+0 records out
1048576 bytes (1.0 MB, 1.0 MiB) copied, 0.009023 s, 116 MB/s
$ file binary.file
binary.file: data
$ echo 123 > text.txt
$ # Let the magic begin
$ find -type f -print0 | \
xargs -0 -I ## bash -c 'file "$#" | grep ASCII &>/dev/null && echo "file is ASCII: $#"' -- ##
Output:
file is ASCII: ./text.txt
Legend: $ is the interactive shell prompt where we enter our commands
You can modify the part after && to call some other script or do some other stuff inline as well, i.e. if that file contains given string, cat the entire file or look for a secondary string in it.
Explanation:
find items that are files
Make xargs feed each item as a line into one liner bash
command/script
file checks type of file by magic byte, grep checks if ASCII
exists, if so, then after && your next command executes.
find prints results null separated, this is good to escape
filenames with spaces and meta-characters in it.
xargs , using -0 option, reads them null separated, -I ##
takes each record and uses as positional parameter/args to bash
script.
-- for bash ensures whatever comes after it is an argument even
if it starts with - like -c which could otherwise be interpreted
as bash option
If you need to find types other than ASCII, simply replace grep ASCII with other type, like grep "PDF document, version 1.4"
find . -type f | xargs file | grep "ASCII text" | awk -F: '{print $1}'
Use find command to list all files, use file command to verify they are text (not tar,key), finally use awk command to filter and print the result.
How about this
find . -type f|xargs grep "needle text"

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