how can I print out the name of each file in a certain directory with a specific extension?
Here's what I have so far:
#!/bin/sh
DIR="~/Desktop"
SUFFIX="in"
for file in $DIR/*.$SUFFIX
do
if [ -f $file ]; then
echo $file
fi
done
Unfortunately it doesn't work.
What's wrong with it?
In your DIR="~/Desktop" the "~" not expanded, because it is in "".
remove the "". DIR=~/Desktop
You could use find with -type f
#!/bin/sh
DIR="~/Desktop"
SUFFIX="in"
find "$DIR" -maxdepth 1 -type f -name "*.${SUFFIX}" -exec somecommand {} \;
For your information: "file" in Unix systems is typically the name of a command.
Its purpose is to analyze the files given as argument and infer the format. Example:
$ file entries.jar
entries.jar: Zip archive data, at least v2.0 to extract
for file in `ls $DIR/*.$SUFFIX`
Note the ls and backticks
Related
I am currently working on an auto grading script for a class project. It has to be able to search any number of given directories lets say
for example
usr/autograder/jdoe/
jdoe contains two files house.c and readme.txt.
I need to create a file in jdoe called jdoe.pdf
Currently i'm using this line of code below to get the path to where i need to create the file. Where $1 is user input of the path containing the projects the auto grader will grade.
find $1 -name "*.txt" -exec sh -c "dirname {}"
When I try adding /somename.pdf to the end of this statement I get readme.txt/somename.pdf
along with another -exec to get the name for the file.
\; -exec sh -c "dirname {} xargs -n 1 basename" \;
I'm having problems combining these two into one working statement.
I'm new to unix programming and would appreciate any advice or help even if it means re-writing the code using different unix tools.
The main question here is how do I create files in a path other than the directory I call my script from. Thanks in advance.
How about this?
find "$1" -name "*.txt" -exec bash -c 'd=$(dirname "$1"); touch $d"/"$(basename "$d").pdf' - {} \;
You can create files in another path using change directory command (cd).
If you start your script in usr/autograder/script and want to change to usr/autograder/jdoe you can change directory with shell command cd ../jdoe (relative) or cd usr/autograder/jdoe (absolute).
Now you are in the directory of usr/autograder/jdoe and you are able to create files in this directory, for example gedit readme.txt will open gedit and creates the file in usr/autograder/jdoe.
The simplest way is to loop over the files returned by find and then do whatever you need to do.
For example:
find "$1" -type f -name "*.txt" -print0 | while IFS= read -r -d $'\0' filename; do
dir=$(dirname "$filename")
# create pdf file
touch "$dir/${dir##*/}.pdf"
done
(Note the use of find -print0 to correctly handle filenames containing whitespace and newline characters.)
Is this what you are looking for?
function process_file {
dir=$(dirname "$1")
name=$(basename "$1")
echo name is $name and dir is $dir;
cd "$dir"
touch "${dir##*/}.pdf" # or anything else
}
# export the function, so that it is known in the child processes
export -f process_file
find . -name '*.txt' -exec bash -c "process_file '{}'" \;
I want to prepend text to the name of every file of a certain type - in this case .txt files - located in the current directory or a sub-directory.
I have tried:
find -L . -type f -name "*.txt" -exec mv "{}" "PrependedTextHere{}" \;
The problem with this is dealing with the ./ part of the path that comes with the {} reference.
Any help or alternative approaches appreciated.
You can do something like this
find -L . -type f -name "*.txt" -exec bash -c 'echo "$0" "${0%/*}/PrependedTextHere${0##*/}"' {} \;
Where
bash -c '...' executes the command
$0 is the first argument passed in, in this case {} -- the full filename
${0%/*} removes everything including and after the last / in the filename
${0##*/} removes everything before and including the last / in the filename
Replace the echo with a mv once you're satisfied it's working.
Are you just trying to move the files to a new file name that has Prepend before it?
for F in *.txt; do mv "$F" Prepend"$F"; done
Or do you want it to handle subdirectories and prepend between the directory and file name:
dir1/PrependA.txt
dir2/PrependB.txt
Here's a quick shot at it. Let me know if it helps.
for file in $(find -L . -type f -name "*.txt")
do
parent=$(echo $file | sed "s=\(.*/\).*=\1=")
name=$(echo $file | sed "s=.*/\(.*\)=\1=")
mv "$file" "${parent}PrependedTextHere${name}"
done
This ought to work, as long file names does not have new line character(s). In such case make the find to use -print0 and IFS to have null.
#!/bin/sh
IFS='
'
for I in $(find -L . -name '*.txt' -print); do
echo mv "$I" "${I%/*}/prepend-${I##*/}"
done
p.s. Remove the echo to make the script effective, it's there to avoid accidental breakage for people who randomly copy paste stuff from here to their shell.
I have several directories with a pattern:
$find -name "*.out"
./trnascanse.out
./darn.out
./blast_rnaz.out
./erpin.out
./rnaspace_cli.out
./yass.out
./atypicalgc.out
./blast.out
./combine.out
./infernal.out
./ecoli.out
./athaliana.out
./yass_carnac.out
./rnammer.out
I can get the list into a file find -name "*.out" > files because I want to create for each directory a file ending with .ref instead of .out : trnascanse.ref, darn.ref, blast_rnaz.refand so on.
I would say that this is possible with some grep and touch but I don't know how to do it. Any idea? Or just create each one manually is the only way (as I did with this directories). Thanks
Here's one way:
for d in *.out ; do echo touch "${d%.out}.ref" ; done
The ${d%.out} expands $d and removes the trailing .out. Read about it in the bash man page.
If the output of above one-liner looks ok, pipe it to sh , or remove the echo and re-run it.
Use this:
find -maxdepth 1 -type d -printf "%f" -exec bash -c "mkdir $(echo '{}' | sed 's/\.out$//').ref" \;
i have the following bash script on my server:
today=$(date +"%Y-%m-%d")
find /backups/www -type f -mtime -1|xargs tar uf /daily/backup-$today.tar
as you can see it creates backups of files modified/created in the last 24h. However if no files are found, it creates corrupted tar file. I would like to wrap it in if..fi statement so id doesn't create empty/corrupted tar files.
Can someone help me modify this script?
Thanks
You can check if result is ok then check if result is empty :
today=$(date +"%Y-%m-%d")
results=`find /backups/www -type f -mtime -1`
if [[ 0 == $? ]] ; then
if [[ -z $results ]] ; then
echo "No files found"
else
tar uf /daily/backup-$today.tar $results
fi
else
echo "Search failed"
fi
find /backups/www -type f -mtime -1 -exec tar uf /daily/backup-$today.tar {} +
Using -exec is preferable to xargs. There's no pipeline needed and it will handle file names with spaces, newlines, and other unusual characters without extra work. The {} at the end is a placeholder for the file names, and + marks the end of the -exec command (in case there were more arguments to find).
As a bonus it won't execute the command if no files are found.
One relatively simple trick would be this:
today=$(date +"%Y-%m-%d")
touch /backups/www/.timestamp
find /backups/www -type f -mtime -1|xargs tar uf /daily/backup-$today.tar
That way you're guaranteed to always find at least one file (and it's minimal in size).
xargs -r does nothing if there is no input.
I have a folder with more than 5000 images, all with JPG extension.
What i want to do, is to add recursively the "thumb_" prefix to all images.
I found a similar question: Rename Files and Directories (Add Prefix) but i only want to add the prefix to files with the JPG extension.
One of possibly solutions:
find . -name '*.jpg' -printf "'%p' '%h/thumb_%f'\n" | xargs -n2 echo mv
Principe: find all needed files, and prepare arguments for the standard mv command.
Notes:
arguments for the mv are surrounded by ' for allowing spaces in filenames.
The drawback is: this will not works with filenames what are containing ' apostrophe itself, like many mp3 files. If you need moving more strange filenames check bellow.
the above command is for dry run (only shows the mv commands with args). For real work remove the echo pretending mv.
ANY filename renaming. In the shell you need a delimiter. The problem is, than the filename (stored in a shell variable) usually can contain the delimiter itself, so:
mv $file $newfile #will fail, if the filename contains space, TAB or newline
mv "$file" "$newfile" #will fail, if the any of the filenames contains "
the correct solution are either:
prepare a filename with a proper escaping
use a scripting language what easuly understands ANY filename
Preparing the correct escaping in bash is possible with it's internal printf and %q formatting directive = print quoted. But this solution is long and boring.
IMHO, the easiest way is using perl and zero padded print0, like next.
find . -name \*.jpg -print0 | perl -MFile::Basename -0nle 'rename $_, dirname($_)."/thumb_".basename($_)'
The above using perl's power to mungle the filenames and finally renames the files.
Beware of filenames with spaces in (the for ... in ... expression trips over those), and be aware that the result of a find . ... will always start with ./ (and hence try to give you names like thumb_./file.JPG which isn't quite correct).
This is therefore not a trivial thing to get right under all circumstances. The expression I've found to work correctly (with spaces, subdirs and all that) is:
find . -iname \*.JPG -exec bash -c 'mv "$1" "`echo $1 | sed \"s/\(.*\)\//\1\/thumb/\"`"' -- '{}' \;
Even that can fall foul of certain names (with quotes in) ...
In OS X 10.8.5, find does not have the -printf option. The port that contained rename seemed to depend upon a WebkitGTK development package that was taking hours to install.
This one line, recursive file rename script worked for me:
find . -iname "*.jpg" -print | while read name; do cur_dir=$(dirname "$name"); cur_file=$(basename "$name"); mv "$name" "$cur_dir/thumb_$cur_file"; done
I was actually renaming CakePHP view files with an 'admin_' prefix, to move them all to an admin section.
You can use that same answer, just use *.jpg, instead of just *.
for file in *.JPG; do mv $file thumb_$file; done
if it's multiple directory levels under the current one:
for file in $(find . -name '*.JPG'); do mv $file $(dirname $file)/thumb_$(basename $file); done
proof:
jcomeau#intrepid:/tmp$ mkdir test test/a test/a/b test/a/b/c
jcomeau#intrepid:/tmp$ touch test/a/A.JPG test/a/b/B.JPG test/a/b/c/C.JPG
jcomeau#intrepid:/tmp$ cd test
jcomeau#intrepid:/tmp/test$ for file in $(find . -name '*.JPG'); do mv $file $(dirname $file)/thumb_$(basename $file); done
jcomeau#intrepid:/tmp/test$ find .
.
./a
./a/b
./a/b/thumb_B.JPG
./a/b/c
./a/b/c/thumb_C.JPG
./a/thumb_A.JPG
jcomeau#intrepid:/tmp/test$
Use rename for this:
rename 's/(\w{1})\.JPG$/thumb_$1\.JPG/' `find . -type f -name *.JPG`
For only jpg files in current folder
for f in `ls *.jpg` ; do mv "$f" "PRE_$f" ; done