Grep in bash script giving no results - bash

I wanted to make a little script to save me some typing, but unfortunately I get no output:
#!/bin/bash
grep -Hnr \"$1\" --include \"*cpp\" --include \"*h\" $2
I played quite a lot with echo and different use of quotes, and convinced myself that line really expands into what I want, but the only way I could actually get any output is with this:
#!/bin/bash
GREP="grep -Hnr \"$1\" --include \"*cpp\" --include \"*h\" $2"
echo $GREP | bash
An example usage would be:
srcgrep "dynamic_cast" src
I've tried this in a simple example directory to rule out anything weird with links, permissions, etc.
So, of course I can just use the second, but any idea what's wrong in the first case? Thanks.
$ grep -V
grep (GNU grep) 2.5.1
...
$ bash --version
GNU bash, version 3.2.25(1)-release (x86_64-redhat-linux-gnu)
...

Why not just:
#!/bin/bash
grep -Hnr "$1" --include "*cpp" --include "*h" $2
?

So, GNU or someone's found a way to screw up grep with completely inappropriate options. Awesome. They really should have considered the UNIX philosophy of "Do one thing and do it well". grep is for searching for text in files, it's not for finding files. There's a perfectly good command with a somewhat obvious name for FINDing files.
find "$2" -name '*cpp' -o -name '*h' -exec grep -Hnr "$1" {} \;
assuming "$2" in your posted example is a directory name instead of a file name as you'd expect grep to work on.

Related

Check if any of the files within a folder contain a pattern then return filename

I'm writing a script that aim to automate the fulfill of some variables and I'm looking for help to achieve this:
I have a nginx sites-enabled folder which contain some reverses proxied sites.
I need to:
check if a pattern $var1 is found in any of the files in "/volume1/nginx/sites-enabled/"
return the name of the file containing $var1 as $var2
Many thanks for your attention and help!
I have found some lines but none try any files in a folder
if grep -q $var1 "/volume1/nginx/sites-enabled/testfile"; then
echo "found"
fi
find and grep can be used to produce a list of matching files:
find /volume1/nginx/sites-enabled/ -type f -exec grep -le "${var1}" {} +
The ‘trick’ is using find’s -exec and grep’s -l.
If you only want the filenames you could use:
find /volume1/nginx/sites-enabled/ -type f -exec grep -qe "${var1}" {} \; -exec basename {} \;
If you want to assign the result to a variable use command substitution ($()):
var2="$(find …)"
Don’t forget to quote your variables!
This command is the most traditional and efficient one which works on any Unix
without the requirement to have GNU versions of grep with special features.
The efficiency is, that xargs feeds the grep command as many filenames as arguments as it is possible according to the limits of the system (how long a shell command may be) and it excecutes the grep command by this only as least as possible.
With the -l option of grep it shows you only the filename once on a successful pattern search.
find /path -type f -print | xargs grep -l pattern
Assuming you have GNU Grep, this will store all files containing the contents of $var1 in an array $var2.
for file in /volume1/nginx/sites-enabled/*
do
if grep --fixed-strings --quiet "$var1" "$file"
then
var2+=("$file")
fi
done
This will loop through NUL-separated paths:
while IFS= read -d'' -r -u9 path
do
…something with "$path"
done 9< <(grep --fixed-strings --files-without-match --recursive "$var1" /volume1/nginx/sites-enabled)

Bash: recursively rename part of a file [duplicate]

I want to go through a bunch of directories and rename all files that end in _test.rb to end in _spec.rb instead. It's something I've never quite figured out how to do with bash so this time I thought I'd put some effort in to get it nailed. I've so far come up short though, my best effort is:
find spec -name "*_test.rb" -exec echo mv {} `echo {} | sed s/test/spec/` \;
NB: there's an extra echo after exec so that the command is printed instead of run while I'm testing it.
When I run it the output for each matched filename is:
mv original original
i.e. the substitution by sed has been lost. What's the trick?
To solve it in a way most close to the original problem would be probably using xargs "args per command line" option:
find . -name "*_test.rb" | sed -e "p;s/test/spec/" | xargs -n2 mv
It finds the files in the current working directory recursively, echoes the original file name (p) and then a modified name (s/test/spec/) and feeds it all to mv in pairs (xargs -n2). Beware that in this case the path itself shouldn't contain a string test.
This happens because sed receives the string {} as input, as can be verified with:
find . -exec echo `echo "{}" | sed 's/./foo/g'` \;
which prints foofoo for each file in the directory, recursively. The reason for this behavior is that the pipeline is executed once, by the shell, when it expands the entire command.
There is no way of quoting the sed pipeline in such a way that find will execute it for every file, since find doesn't execute commands via the shell and has no notion of pipelines or backquotes. The GNU findutils manual explains how to perform a similar task by putting the pipeline in a separate shell script:
#!/bin/sh
echo "$1" | sed 's/_test.rb$/_spec.rb/'
(There may be some perverse way of using sh -c and a ton of quotes to do all this in one command, but I'm not going to try.)
you might want to consider other way like
for file in $(find . -name "*_test.rb")
do
echo mv $file `echo $file | sed s/_test.rb$/_spec.rb/`
done
I find this one shorter
find . -name '*_test.rb' -exec bash -c 'echo mv $0 ${0/test.rb/spec.rb}' {} \;
You can do it without sed, if you want:
for i in `find -name '*_test.rb'` ; do mv $i ${i%%_test.rb}_spec.rb ; done
${var%%suffix} strips suffix from the value of var.
or, to do it using sed:
for i in `find -name '*_test.rb'` ; do mv $i `echo $i | sed 's/test/spec/'` ; done
You mention that you are using bash as your shell, in which case you don't actually need find and sed to achieve the batch renaming you're after...
Assuming you are using bash as your shell:
$ echo $SHELL
/bin/bash
$ _
... and assuming you have enabled the so-called globstar shell option:
$ shopt -p globstar
shopt -s globstar
$ _
... and finally assuming you have installed the rename utility (found in the util-linux-ng package)
$ which rename
/usr/bin/rename
$ _
... then you can achieve the batch renaming in a bash one-liner as follows:
$ rename _test _spec **/*_test.rb
(the globstar shell option will ensure that bash finds all matching *_test.rb files, no matter how deeply they are nested in the directory hierarchy... use help shopt to find out how to set the option)
The easiest way:
find . -name "*_test.rb" | xargs rename s/_test/_spec/
The fastest way (assuming you have 4 processors):
find . -name "*_test.rb" | xargs -P 4 rename s/_test/_spec/
If you have a large number of files to process, it is possible that the list of filenames piped to xargs would cause the resulting command line to exceed the maximum length allowed.
You can check your system's limit using getconf ARG_MAX
On most linux systems you can use free -b or cat /proc/meminfo to find how much RAM you have to work with; Otherwise, use top or your systems activity monitor app.
A safer way (assuming you have 1000000 bytes of ram to work with):
find . -name "*_test.rb" | xargs -s 1000000 rename s/_test/_spec/
Here is what worked for me when the file names had spaces in them. The example below recursively renames all .dar files to .zip files:
find . -name "*.dar" -exec bash -c 'mv "$0" "`echo \"$0\" | sed s/.dar/.zip/`"' {} \;
For this you don't need sed. You can perfectly get alone with a while loop fed with the result of find through a process substitution.
So if you have a find expression that selects the needed files, then use the syntax:
while IFS= read -r file; do
echo "mv $file ${file%_test.rb}_spec.rb" # remove "echo" when OK!
done < <(find -name "*_test.rb")
This will find files and rename all of them striping the string _test.rb from the end and appending _spec.rb.
For this step we use Shell Parameter Expansion where ${var%string} removes the shortest matching pattern "string" from $var.
$ file="HELLOa_test.rbBYE_test.rb"
$ echo "${file%_test.rb}" # remove _test.rb from the end
HELLOa_test.rbBYE
$ echo "${file%_test.rb}_spec.rb" # remove _test.rb and append _spec.rb
HELLOa_test.rbBYE_spec.rb
See an example:
$ tree
.
├── ab_testArb
├── a_test.rb
├── a_test.rb_test.rb
├── b_test.rb
├── c_test.hello
├── c_test.rb
└── mydir
└── d_test.rb
$ while IFS= read -r file; do echo "mv $file ${file/_test.rb/_spec.rb}"; done < <(find -name "*_test.rb")
mv ./b_test.rb ./b_spec.rb
mv ./mydir/d_test.rb ./mydir/d_spec.rb
mv ./a_test.rb ./a_spec.rb
mv ./c_test.rb ./c_spec.rb
if you have Ruby (1.9+)
ruby -e 'Dir["**/*._test.rb"].each{|x|test(?f,x) and File.rename(x,x.gsub(/_test/,"_spec") ) }'
In ramtam's answer which I like, the find portion works OK but the remainder does not if the path has spaces. I am not too familiar with sed, but I was able to modify that answer to:
find . -name "*_test.rb" | perl -pe 's/^((.*_)test.rb)$/"\1" "\2spec.rb"/' | xargs -n2 mv
I really needed a change like this because in my use case the final command looks more like
find . -name "olddir" | perl -pe 's/^((.*)olddir)$/"\1" "\2new directory"/' | xargs -n2 mv
I haven't the heart to do it all over again, but I wrote this in answer to Commandline Find Sed Exec. There the asker wanted to know how to move an entire tree, possibly excluding a directory or two, and rename all files and directories containing the string "OLD" to instead contain "NEW".
Besides describing the how with painstaking verbosity below, this method may also be unique in that it incorporates built-in debugging. It basically doesn't do anything at all as written except compile and save to a variable all commands it believes it should do in order to perform the work requested.
It also explicitly avoids loops as much as possible. Besides the sed recursive search for more than one match of the pattern there is no other recursion as far as I know.
And last, this is entirely null delimited - it doesn't trip on any character in any filename except the null. I don't think you should have that.
By the way, this is REALLY fast. Look:
% _mvnfind() { mv -n "${1}" "${2}" && cd "${2}"
> read -r SED <<SED
> :;s|${3}\(.*/[^/]*${5}\)|${4}\1|;t;:;s|\(${5}.*\)${3}|\1${4}|;t;s|^[0-9]*[\t]\(mv.*\)${5}|\1|p
> SED
> find . -name "*${3}*" -printf "%d\tmv %P ${5} %P\000" |
> sort -zg | sed -nz ${SED} | read -r ${6}
> echo <<EOF
> Prepared commands saved in variable: ${6}
> To view do: printf ${6} | tr "\000" "\n"
> To run do: sh <<EORUN
> $(printf ${6} | tr "\000" "\n")
> EORUN
> EOF
> }
% rm -rf "${UNNECESSARY:=/any/dirs/you/dont/want/moved}"
% time ( _mvnfind ${SRC=./test_tree} ${TGT=./mv_tree} \
> ${OLD=google} ${NEW=replacement_word} ${sed_sep=SsEeDd} \
> ${sh_io:=sh_io} ; printf %b\\000 "${sh_io}" | tr "\000" "\n" \
> | wc - ; echo ${sh_io} | tr "\000" "\n" | tail -n 2 )
<actual process time used:>
0.06s user 0.03s system 106% cpu 0.090 total
<output from wc:>
Lines Words Bytes
115 362 20691 -
<output from tail:>
mv .config/replacement_word-chrome-beta/Default/.../googlestars \
.config/replacement_word-chrome-beta/Default/.../replacement_wordstars
NOTE: The above function will likely require GNU versions of sed and find to properly handle the find printf and sed -z -e and :;recursive regex test;t calls. If these are not available to you the functionality can likely be duplicated with a few minor adjustments.
This should do everything you wanted from start to finish with very little fuss. I did fork with sed, but I was also practicing some sed recursive branching techniques so that's why I'm here. It's kind of like getting a discount haircut at a barber school, I guess. Here's the workflow:
rm -rf ${UNNECESSARY}
I intentionally left out any functional call that might delete or destroy data of any kind. You mention that ./app might be unwanted. Delete it or move it elsewhere beforehand, or, alternatively, you could build in a \( -path PATTERN -exec rm -rf \{\} \) routine to find to do it programmatically, but that one's all yours.
_mvnfind "${#}"
Declare its arguments and call the worker function. ${sh_io} is especially important in that it saves the return from the function. ${sed_sep} comes in a close second; this is an arbitrary string used to reference sed's recursion in the function. If ${sed_sep} is set to a value that could potentially be found in any of your path- or file-names acted upon... well, just don't let it be.
mv -n $1 $2
The whole tree is moved from the beginning. It will save a lot of headache; believe me. The rest of what you want to do - the renaming - is simply a matter of filesystem metadata. If you were, for instance, moving this from one drive to another, or across filesystem boundaries of any kind, you're better off doing so at once with one command. It's also safer. Note the -noclobber option set for mv; as written, this function will not put ${SRC_DIR} where a ${TGT_DIR} already exists.
read -R SED <<HEREDOC
I located all of sed's commands here to save on escaping hassles and read them into a variable to feed to sed below. Explanation below.
find . -name ${OLD} -printf
We begin the find process. With find we search only for anything that needs renaming because we already did all of the place-to-place mv operations with the function's first command. Rather than take any direct action with find, like an exec call, for instance, we instead use it to build out the command-line dynamically with -printf.
%dir-depth :tab: 'mv '%path-to-${SRC}' '${sed_sep}'%path-again :null delimiter:'
After find locates the files we need it directly builds and prints out (most) of the command we'll need to process your renaming. The %dir-depth tacked onto the beginning of each line will help to ensure we're not trying to rename a file or directory in the tree with a parent object that has yet to be renamed. find uses all sorts of optimization techniques to walk your filesystem tree and it is not a sure thing that it will return the data we need in a safe-for-operations order. This is why we next...
sort -general-numerical -zero-delimited
We sort all of find's output based on %directory-depth so that the paths nearest in relationship to ${SRC} are worked first. This avoids possible errors involving mving files into non-existent locations, and it minimizes need to for recursive looping. (in fact, you might be hard-pressed to find a loop at all)
sed -ex :rcrs;srch|(save${sep}*til)${OLD}|\saved${SUBSTNEW}|;til ${OLD=0}
I think this is the only loop in the whole script, and it only loops over the second %Path printed for each string in case it contains more than one ${OLD} value that might need replacing. All other solutions I imagined involved a second sed process, and while a short loop may not be desirable, certainly it beats spawning and forking an entire process.
So basically what sed does here is search for ${sed_sep}, then, having found it, saves it and all characters it encounters until it finds ${OLD}, which it then replaces with ${NEW}. It then heads back to ${sed_sep} and looks again for ${OLD}, in case it occurs more than once in the string. If it is not found, it prints the modified string to stdout (which it then catches again next) and ends the loop.
This avoids having to parse the entire string, and ensures that the first half of the mv command string, which needs to include ${OLD} of course, does include it, and the second half is altered as many times as is necessary to wipe the ${OLD} name from mv's destination path.
sed -ex...-ex search|%dir_depth(save*)${sed_sep}|(only_saved)|out
The two -exec calls here happen without a second fork. In the first, as we've seen, we modify the mv command as supplied by find's -printf function command as necessary to properly alter all references of ${OLD} to ${NEW}, but in order to do so we had to use some arbitrary reference points which should not be included in the final output. So once sed finishes all it needs to do, we instruct it to wipe out its reference points from the hold-buffer before passing it along.
AND NOW WE'RE BACK AROUND
read will receive a command that looks like this:
% mv /path2/$SRC/$OLD_DIR/$OLD_FILE /same/path_w/$NEW_DIR/$NEW_FILE \000
It will read it into ${msg} as ${sh_io} which can be examined at will outside of the function.
Cool.
-Mike
I was able handle filenames with spaces by following the examples suggested by onitake.
This doesn't break if the path contains spaces or the string test:
find . -name "*_test.rb" -print0 | while read -d $'\0' file
do
echo mv "$file" "$(echo $file | sed s/test/spec/)"
done
This is an example that should work in all cases.
Works recursiveley, Need just shell, and support files names with spaces.
find spec -name "*_test.rb" -print0 | while read -d $'\0' file; do mv "$file" "`echo $file | sed s/test/spec/`"; done
$ find spec -name "*_test.rb"
spec/dir2/a_test.rb
spec/dir1/a_test.rb
$ find spec -name "*_test.rb" | xargs -n 1 /usr/bin/perl -e '($new=$ARGV[0]) =~ s/test/spec/; system(qq(mv),qq(-v), $ARGV[0], $new);'
`spec/dir2/a_test.rb' -> `spec/dir2/a_spec.rb'
`spec/dir1/a_test.rb' -> `spec/dir1/a_spec.rb'
$ find spec -name "*_spec.rb"
spec/dir2/b_spec.rb
spec/dir2/a_spec.rb
spec/dir1/a_spec.rb
spec/dir1/c_spec.rb
Your question seems to be about sed, but to accomplish your goal of recursive rename, I'd suggest the following, shamelessly ripped from another answer I gave here:recursive rename in bash
#!/bin/bash
IFS=$'\n'
function RecurseDirs
{
for f in "$#"
do
newf=echo "${f}" | sed -e 's/^(.*_)test.rb$/\1spec.rb/g'
echo "${f}" "${newf}"
mv "${f}" "${newf}"
f="${newf}"
if [[ -d "${f}" ]]; then
cd "${f}"
RecurseDirs $(ls -1 ".")
fi
done
cd ..
}
RecurseDirs .
More secure way of doing rename with find utils and sed regular expression type:
mkdir ~/practice
cd ~/practice
touch classic.txt.txt
touch folk.txt.txt
Remove the ".txt.txt" extension as follows -
cd ~/practice
find . -name "*txt" -execdir sh -c 'mv "$0" `echo "$0" | sed -r 's/\.[[:alnum:]]+\.[[:alnum:]]+$//'`' {} \;
If you use the + in place of ; in order to work on batch mode, the above command will rename only the first matching file, but not the entire list of file matches by 'find'.
find . -name "*txt" -execdir sh -c 'mv "$0" `echo "$0" | sed -r 's/\.[[:alnum:]]+\.[[:alnum:]]+$//'`' {} +
Here's a nice oneliner that does the trick.
Sed can't handle this right, especially if multiple variables are passed by xargs with -n 2.
A bash substition would handle this easily like:
find ./spec -type f -name "*_test.rb" -print0 | xargs -0 -I {} sh -c 'export file={}; mv $file ${file/_test.rb/_spec.rb}'
Adding -type -f will limit the move operations to files only, -print 0 will handle empty spaces in paths.
I share this post as it is a bit related to question. Sorry for not providing more details. Hope it helps someone else.
http://www.peteryu.ca/tutorials/shellscripting/batch_rename
This is my working solution:
for FILE in {{FILE_PATTERN}}; do echo ${FILE} | mv ${FILE} $(sed 's/{{SOURCE_PATTERN}}/{{TARGET_PATTERN}}/g'); done

How to get the grep command to search a specified directory?

I am trying to create a bash command that uses grep to search arguments in a specified directory. How would I do this. At the moment it only searches for the current directory. I have tried the following but it doesn't work:
ls $directoryName -l | grep "$1"
I'm sure there's a better way do do this but
ls -lah $directoryName > /usr/tmp/test
grep $1 /usr/tmp/test
rm /usr/tmp/test
Edit: You might have better luck using find though.
find $directoryName -name $1
Working example:
grep -e "Exec" /usr/share/applications/*
The following example will search recursively (including in sub-folders and hidden files) for an argument or pattern in a literal way (it will search for '$1' literally, not allowing substitution):
grep -re '$1' /folder/folder
Now, if you want to search for the value of the argument, then the code below would allow for substitution and do that:
grep -re "$1" /folder/folder

grep --include command doesn't work in OSX Zsh

I am following the best answer on How do I find all files containing specific text on Linux? to search string in my project.
This is my command grep --include=*.rb -rnw . -e "pattern"
Zsh tells me that zsh: no matches found: --include=*.rb
It seems that grep doesn't support --include option.
When I type grep --help, it returns
usage: grep [-abcDEFGHhIiJLlmnOoPqRSsUVvwxZ] [-A num] [-B num] [-C[num]]
[-e pattern] [-f file] [--binary-files=value] [--color=when]
[--context[=num]] [--directories=action] [--label] [--line-buffered]
[--null] [pattern] [file ...]
no --include here.
Is my grep version too old? Or is there something wrong with my command?
FreeBSD/macOS grep does support the --include option (see man grep; it's unfortunate that the command-line help (grep -h) doesn't list this option), but your problem is that the option argument, *.rb, is unquoted.
As a result, it is your shell, zsh, that attempts to pathname-expand --include=*.rb up front, and fails, because the current directory contains no files with names matching glob pattern *.rb.
grep never even gets to execute.
Since your intent is to pass *.rb unmodified to grep, you must quote it:
grep --include='*.rb' -rnw . -e "pattern"
To include multiple globs:
Pass an --include option for each; e.g.:
grep --include='*.rb' --include=='*.h*' -rnw . -e "pattern"
Alternatively, in shells that support brace expansion - notably bash, ksh, and zsh - you can let your shell create these multiple options for you, as follows - note the selective quoting (see this answer for a detailed explanation):
grep '--include=*.'{rb,'h*'} -rnw . -e "pattern"
If your grep does not support --include, and you don't want to install GNU grep just for this, there are a number of portable ways to perform the same operation. Off the top of my head, try
find . -type f -name '*.rb' -exec grep -nw "pattern" /dev/null {} \;
The find command traverses the directory (like grep -r) looking for files named *.rb (like the --include option) and the /dev/null is useful because grep shows a slightly different output format when you run it on multiple files.
This is slightly inefficient because it runs a separate grep for each file. If it's too slow, look into xargs (or use find -exec ... {} \+ instead of ... {} \; if your find supports that). This is a very common task; you should easily find thousands of examples.
You might also want to consider ack which is a popular and somewhat more user-friendly alternative. It is self-contained, so "installation" amounts to copying it to your $HOME/bin.

How do I get a list of all available shell commands

In a typical Linux shell (bash) it is possible to to hit tab twice, to get a list of all available shell commands.
Is there a command which has the same behaviour? I want to pipe it into grep and search it.
You could use compgen. For example:
compgen -c
You also could grep it, like this:
compgen -c | grep top$
Source: http://www.cyberciti.biz/open-source/command-line-hacks/compgen-linux-command/
You can list the directories straight from $PATH if you tweak the field separator first. The parens limit the effect to the one command, so use: (...) | grep ...
(IFS=': '; ls -1 $PATH)
"tab" twice & "y" prints all files in the paths of $PATH. So just printing all files in PATH is sufficient.
Just type this in the shell:
# printf "%s\n" ${PATH//:/\/* } > my_commands
This redirect all the commands to a file "my_commands".
List all the files in your PATH variable (ls all the directories in the PATH). The default user and system commands will be in /bin and /sbin respectively but on installing some software we will add them to some directory and link it using PATH variable.
There may be things on your path which aren't actually executable.
#!/bin/sh
for d in ${PATH//:/ }; do
for f in "$d"/*; do
test -x "$f" && echo -n "$f "
done
done
echo ""
This will also print paths, of course. If you only want unqualified filenames, it should be easy to adapt this.
Funny, StackOverflow doesn't know how to handle syntax highlighting for this. :-)
tabtaby
Similar to #ghoti, but using find:
#!/bin/sh
for d in ${PATH//:/ }; do
find $d -maxdepth 1 -type f -executable
done
Bash uses a builtin command named 'complete' to implement the tab feature.
I don't have the details to hand, but the should tell you all you need to know:
help complete
(IFS=':'; find $PATH -maxdepth 1 -type f -executable -exec basename {} \; | sort | uniq)
It doesn't include shell builtins though.
An answer got deleted, I liked it most, so I'm trying to repost it:
compgen is of course better
echo $PATH | tr ':' '\n' | xargs -n 1 ls -1
I found this to be the most typical shell thing, I think it works also with other shells (which I doubt with things like IFS=':' )
Clearly, there maybe problems, if the file is not an executable, but I think for my question, that is enough - I just want to grep my output - which means searching for some commands.

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