given a directory $HOME/foo/ with files in it.
the command:
find $HOME/foo -type f -exec md5deep -bre {} \;
works fine and hashes the files.
but, creating a variable for -exec does not seem to work:
md5="md5deep -bre"
find $HOME/foo -type f -exec "$md5" {} \;
returns: find: md5deep -bre: No such file or directory
why?
Since you are enclosing your variable in double quotes, the entire string gets sent to find as a single token following -exec and find treats it as the name of the command. To resolve the issue, simply remove the double quotes around your variable:
find "$HOME/foo" -type f -exec $md5 {} \;
In general, it is not good to store commands in shell variables. See BashFAQ/050.
Use an array.
md5Cmd=(md5deep -bre)
find "$HOME/foo" -type f -exec "${md5Cmd[#]}" {} \;
Better still, make the whole -exec statement optional:
md5Cmd=( -exec md5deep -bre {} \; )
find "$HOME/foo" -type f "${md5Cmd[#]}"
I have found the syntax for find -exec a bit weird (with several pitfalls as the ones #codeforester has mentioned).
So, as an alternative, i tend to separate the search part from the action part by piping the output of find (or grep) to a proper xargs process.
For example, i find it more readable (-n1 for using exactly 1 argument per command):
find $HOME/foo -type f | xargs -n1 md5deep -bre
Related
I'm trying to write one line of code that finds all .sh files in the current directory and its subdirectories, and print them without the .sh extension (preferably without the path too).
I think I got the find command down. I tried using the output of
find . -type f -iname "*.sh" -print
as input for echo, and formatting it along these lines
echo "${find_output%.sh}"
However, I cannot get it to work in one line, without variable assigment.
I got inspiration from this answer on stackoverflow https://stackoverflow.com/a/18639136/15124805
to use this line:
echo "${$( find . -type f -iname "*.sh" -print)%.sh}"
But I get this error:
ash: ${$( find . -type f -iname "*.sh" -print)%.sh}: bad substitution
I also tried using xargs
find . -type f -iname "*.sh" -print |"${xargs%.sh}" echo
But I get a "command not found error" -probably I didn't use xargs correctly, but I'm not sure how I could improve this or if it's the right way to go.
How can I make this work?
That's the classic useless use of echo. You simply want
find . -type f -iname "*.sh" -exec basename {} .sh \;
If you have GNU find, you can also do this with -printf.
However, basename only matches .sh literally, so if you really expect extensions with different variants of capitalization, you need a different approach.
For the record, the syntax you tried to use for xargs would attempt to use the value of a variable named xargs. The correct syntax would be something like
find . -type f -iname "*.sh" -print |
xargs -n 1 sh -c 'echo "${1%.[Ss][Hh]}"' _
but that's obviously rather convoluted. In some more detail, you need sh because the parameter expansion you are trying to use is a feature of the shell, not of echo (or xargs, or etc).
(You can slightly optimize by using a loop:
find . -type f -iname "*.sh" -print |
xargs sh -c 'for f; do
echo "${f%.[Ss][Hh]}"
done' _
but this is still not robust for all file names; see also https://mywiki.wooledge.org/BashFAQ/020 for probably more than you realized you needed to know about this topic. If you have GNU find and GNU xargs, you can use find ... -print0 | xargs -r0)
These are bash commands that are used to convert tabs to spaces.
Here's the link to the original stackoverflow post.
This one uses \; at the end of the command
find /path/to/directory -type f -iname '*.js' -exec sed -ie 's|\t| |g' '{}' \;
This one uses + instead of \;.
find /path/to/directory -type f -iname '*.js' -exec sed -ie 's|\t| |g' '{}' '+'
What exactly is the difference between the two?
The \; or + is not related to bash. It's an argument to the find command, specifically to find's -exec option.
find -exec uses {} to pass the current file name to the specified command, and \; to mark the end of the the command's arguments. The \ is needed because ; by itself is special to bash; by typing \;, you can pass a literal ; character as an argument. (You can also type ';' or ";".)
The + symbol (no \ needed because + is not special to bash) causes find to invoke the specified command with multiple arguments rather than just once, in a manner similar to xargs.
For example, suppose the current directory contains 2 files named abc and xyz. If you type:
find . -type f -exec echo {} \;
it invokes the echo command twice, producing this output:
./abc
./xyz
If you instead type:
find . -type f -exec echo {} +
then find invokes echo just once, with the following output:
./xyz ./abc
For more information, type info find or man find (if the documentation is installed on your system), or you can read the manual online at http://www.gnu.org/software/findutils/manual/html_node/find_html/
I am looking for some help trying to get a command working. I want to find some files only and move them, but when I enter this command:
find /Volumes/NEXSAN/Engine\ Folders/Input/DTO_Proxy/* -type f -mtime +7 -exec mv -v {} /Volumes/NEXSAN/.2BeDeleted4realz/
I get this error
find: -exec: no terminating ";" or "+"
I know I probably have it wrong, but I can't figure out what's missing?
Just terminate the find command with \;, making sure to include the space before the \;.
find /Volumes/NEXSAN/Engine\ Folders/Input/DTO_Proxy/* -type f -mtime +7 -exec mv -v {} /Volumes/NEXSAN/.2BeDeleted4realz/ \;
If you want to correct the find command that you had, it should look like this:
find . -name '*.xml' -exec SetFile -t TEXT {} \;
The *.xml needs to be quoted so it's passed as a parameter to find instead of expanded by the shell. The ; also needs to be escaped so it's passed as part of the parameter to find and not interpreted by the shell.
Keep in mind this will only work for files within the current directory (and subdirectories) and for any new files created, you would need to run the command again.
OK, so simple enough.. I want to recursively search a directory for files with a specific extension - and then perform an action on those files.
# pwdENTER
/dir
# ls -R | grep .txt | xargs -I {} open {} ENTER
The file /dir/reallyinsubfolder.txt does not exist. ⬅ fails (bad)
Not output, but succeeds.. /dir/fileinthisfolder.txt ⬅ opens silently (good)
This does find ALL the files I am interested in… but only OPEN's those which happen to be "1-level" deep. In this case, the attempt to open /dir/reallyinsubfolder.txt fails, as reallyinsubfolder.txt is actually /dir/sub/reallyinsubfolder.txt.
I understand that grep is simply returning the matched filename… which then chokes (in this case), the open command, as it fails to reach down to the correct sub-directory to execute the file..
How do I get grep to return the full path of a match?
How about using the find command -
find /path/to/dir -type f -iname "*.txt" -exec action to perform {} \;
find . -name *.txt -exec open {};
(Decorate with backslashes of your needing)
I believe you're asking the wrong question; parsing ls(1) output in this fashion is far more trouble than it is worth.
What would work far more reliably:
find /dir -name '*.txt' -print0 | xargs -0 open
or
find /dir -name '*.txt' -exec open {} \;
find(1) does not mangle names nearly as much as ls(1) and makes executing programs on matched files far more reliable.
So basically, I have a folder with a bunch of subfolders all with over 100 files in them. I want to take all of the mp3 files (really generic extension since I'll have to do this with jpg, etc.) and move them to a new folder in the original directory. So basically the file structure looks like this:
/.../dir/recup1/file1.mp3
/.../dir/recup2/file2.mp3
... etc.
and I want it to look like this:
/.../dir/music/file1.mp3
/.../dir/music/file2.mp3
... etc.
I figured I would use a bash script that looked along these lines:
#!/bin/bash
STR=`find ./ -type f -name \*.mp3`
FILES=(echo $STR | tr ".mp3 " "\n")
for x in $FILES
do
echo "> [$x]"
done
I just have it echo for now, but eventually I would want to use mv to get it to the correct folder. Obviously this doesn't work though because tr sees each character as a delimiter, so if you guys have a better idea I'd appreciate it.
(FYI, I'm running netbook Ubuntu, so if there's a GUI way akin to Windows' search, I would not be against using it)
If the music folder exists then the following should work -
find /path/to/search -type f -iname "*.mp3" -exec mv {} path/to/music \;
A -exec command must be terminated with a ; (so you usually need to type \; or ';' to avoid interpretion by the shell) or a +. The difference is that with ;, the command is called once per file, with +, it is called just as few times as possible (usually once, but there is a maximum length for a command line, so it might be split up) with all filenames.
You can do it like this:
find /some/dir -type f -iname '*.mp3' -exec mv \{\} /where/to/move/ \;
The \{\} part will be replaced by the found file name/path. The \; part sets the end for the -exec part, it can't be left out.
If you want to print what was found, just add a -print flag like:
find /some/dir -type f -iname '*.mp3' -print -exec mv \{\} /where/to/move/ \;
HTH