Strip leading dot from filenames bash script - linux

I have some files in a bunch of directories that have a leading dot and thus are hidden. I would like to revert that and strip the leading dot.
I was unsuccessful with the following:
for file in `find files/ -type f`;
do
base=`basename $file`
if [ `$base | cut -c1-2` = "." ];
then newname=`$base | cut -c2-`;
dirs=`dirname $file`;
echo $dirs/$newname;
fi
done
Which fails on the condition statement:
[: =: unary operator expected
Furthermore, some files have a space in them and file returns them split.
Any help would be appreciated.

The easiest way to delete something from the start of a variable is to use ${var#pattern}.
$ FILENAME=.bashrc; echo "${FILENAME#.}"
bashrc
$ FILENAME=/etc/fstab; echo "${FILENAME#.}"
/etc/fstab
See the bash man page:
${parameter#word}
${parameter##word}
The word is expanded to produce a pattern just as in pathname expansion. If the pattern matches the beginning of the value of parameter, then the result of the expansion is
the expanded value of parameter with the shortest matching pattern (the ‘‘#’’ case) or the longest matching pattern (the ‘‘##’’ case) deleted.
By the way, with a more selective find command you don't need to do all the hard work. You can have find only match files with a leading dot:
find files/ -type f -name '.*'
Throwing that all together, then:
find files/ -type f -name '.*' -printf '%P\0' |
while read -d $'\0' path; do
dir=$(dirname "$path")
file=$(basename "$path")
mv "$dir/$file" "$dir/${file#.}"
done
Additional notes:
To handle file names with spaces properly you need to quote variable names when you reference them. Write "$file" instead of just $file.
For extra robustness the -printf '\0' and read -d $'\0' use NUL characters as delimiters so even file names with embedded newlines '\n' will work.

find files/ -name '.*' -printf '%f\n'|while read f; do
mv "files/$f" "files/${f#.}"
done

This script works with any file you
can throw at it, even if they have
spaces, newlines or other nefarious
characters in their name.
It works no matter how many subdirectories deep the hidden file is
Unlike other answers thus far, you
don't have to change the rest of the script when you change the path
given to find
*Note: I included an echo so that you can test it like a dry-run. Remove the single echo if you are satisfied with the results.
find . -name '.*' -exec sh -c 'for arg; do d="${arg%/*}"; f=${arg:${#d}}; echo mv "$arg" "$d/${f#.}"; done' _ {} +

Related

How to read out a file line by line and for every line do a search with find and copy the search result to destination?

I hope you can help me with the following problem:
The Situation
I need to find files in various folders and copy them to another folder. The files and folders can contain white spaces and umlauts.
The filenames contain an ID and a string like:
"2022-01-11-02 super important file"
The filenames I need to find are collected in a textfile named ids.txt. This file only contains the IDs but not the whole filename as a string.
What I want to achieve:
I want to read out ids.txt line by line.
For every line in ids.txt I want to do a find search and copy cp the result to destination.
So far I tried:
for n in $(cat ids.txt); do find /home/alex/testzone/ -name "$n" -exec cp {} /home/alex/testzone/output \; ;
while read -r ids; do find /home/alex/testzone -name "$ids" -exec cp {} /home/alex/testzone/output \; ; done < ids.txt
The output folder remains empty. Not using -exec also gives no (search)results.
I was thinking that -name "$ids" is the root cause here. My files contain the ID + a String so I should search for names containing the ID plus a variable string (star)
As argument for -name I also tried "$ids *" "$ids"" *" and so on with no luck.
Is there an argument that I can use in conjunction with find instead of using the star in the -name argument?
Do you have any solution for me to automate this process in a bash script to read out ids.txt file, search the filenames and copy them over to specified folder?
In the end I would like to create a bash script that takes ids.txt and the search-folder and the output-folder as arguments like:
my-id-search.sh /home/alex/testzone/ids.txt /home/alex/testzone/ /home/alex/testzone/output
EDIT:
This is some example content of the ids.txt file where only ids are listed (not the whole filename):
2022-01-11-01
2022-01-11-02
2020-12-01-62
EDIT II:
Going on with the solution from tripleee:
#!/bin/bash
grep . $1 | while read -r id; do
echo "Der Suchbegriff lautet:"$id; echo;
find /home/alex/testzone -name "$id*" -exec cp {} /home/alex/testzone/ausgabe \;
done
In case my ids.txt file contains empty lines the -name "$id*" will be -name * which in turn finds all files and copies all files.
Trying to prevent empty line to be read does not seem to work. They should be filtered by the expression grep . $1 |. What am I doing wrong?
If your destination folder is always the same, the quickest and absolutely most elegant solution is to run a single find command to look for all of the files.
sed 's/.*/-o\n—name\n&*/' ids.txt |
xargs -I {} find -false {} -exec cp {} /home/alex/testzone/output +
The -false predicate is a bit of a hack to allow the list of actual predicates to start with -o (as in "or").
This could fail if ids.txt is too large to fit into a single xargs invocation, or if your sed does not understand \n to mean a literal newline.
(Here's a fix for the latter case:
xargs printf '-o\n-name\n%s*\n' <ids.txt |
...
Still the inherent problem with using xargs find like this is that xargs could split the list between -o and -name or between -name and the actual file name pattern if it needs to run more than one find command to process all the arguments.
A slightly hackish solution to that is to ensure that each pair is a single string, and then separately split them back out again:
xargs printf '-o_-name_%s*\n' <ids.txt |
xargs bash -c 'arr=("$#"); find -false ${arr[#]/-o_-name_/-o -name } -exec cp {} "$0"' /home/alex/testzone/ausgabe
where we temporarily hold the arguments in an array where each file name and its flags is a single item, and then replace the flags into separate tokens. This still won't work correctly if the file names you operate on contain literal shell metacharacters like * etc.)
A more mundane solution fixes your while read attempt by adding the missing wildcard in the -name argument. (I also took the liberty to rename the variable, since read will only read one argument at a time, so the variable name should be singular.)
while read -r id; do
find /home/alex/testzone -name "$id*" -exec cp {} /home/alex/testzone/output \;
done < ids.txt
Please try the following bash script copier.sh
#!/bin/bash
IFS=$'\n' # make newlines the only separator
set -f # disable globbing
file="files.txt" # name of file containing filenames
finish="finish" # destination directory
while read -r n ; do (
du -a | awk '{for(i=2;i<=NF;++i)printf $i" " ; print " "}' | grep $n | sed 's/ *$//g' | xargs -I '{}' cp '{}' $finish
);
done < $file
which copies recursively all the files named in files.txt from . and it's subfiles to ./finish
This new version works even if there are spaces in the directory names or file names.

Get file globs from a file and find these files

I have a file called "file.txt" and it contains globs. Contents:
*.tex
*.pdf
*C*.png
I need to get these extensions from the file and then find the files containging these globs in the current directory (preferably using find, anything else is fine too).
I used
grep "" file.txt | xargs find . -name
but I get this error:
find: paths must precede expression: `*.pdf'
Using Ubuntu
The original code needs the -n 1 argument to be passed to xargs, to pass only one glob to each copy of find, as each glob expression needs to be preceded with a -name (and attached to any other -name expressions with -o, the "or" operator).
More efficient is to run find just once, after constructing an expression that puts all your -name operators on a single command line, separated with -os.
#!/usr/bin/env bash
# ^^^^- MUST be run with bash, not /bin/sh
find_expr=( -false )
while IFS= read -r line; do
find_expr+=( -o -name "$line" )
done <file.txt
find . '(' "${find_expr[#]}" ')' -print

Find & Xargs copy and rename via bash script

I have a folder with images and I need to copy them elsewhere removing special chars in the progress.
Lets say I have this
Folder1/ImageÑ%1.jpg
Folder1/ImageÑ%1-70x70.jpg
Folder1/ImageÑ%2.jpg
Folder1/ImageÑ%2-70x70.jpg
Folder1/ImageÑ%3.jpg
Folder1/ImageÑ%3-100x100.jpg
Folder1/ImageÑ%4.jpg
Folder1/ImageÑ%4-100x100.jpg
And I want to copy just the files that doesn't have "-70x70" or "-100x100" in the name to Folder2 and be like this (without any special char):
Folder2/Image1.jpg
Folder2/Image2.jpg
Folder2/Image3.jpg
Folder2/Image4.jpg
I've managed to copy the files, but I have no clue how to rename the files (and remove the special chars) in the same step. I think it's using SED but I can't figure out how.
find Folder1 -type f -regextype posix-extended \( ! -regex '.+\-[0-9]{2,4}x[0-9]{2,4}\.jpg' \) -print0 | xargs -0 cp -p --target-directory=Folder2
Thanks!
To remove weird characters, I recommend you detox
Then :
find Folder1 \( ! -name 'Image*-70x70*' -a ! -name 'Image*-100x100*' \) |
xargs -i% cp -p % Folder2
edit
find explanations :
the ! character is a negation
-a option is a AND condition
the parenthesis are there to enclose the conditions
Edit2
To do it on the fly like you ask (for substituting weird characters):
find Folder1 \( ! -name 'Image*-70x70*' -a ! -name 'Image*-100x100*' \) \
-exec bash -c '
file=$(echo "$1" | perl -pe "s/\303\221%/_weird_/g")
cp -p "$1" "Folder2/$file"
' -- {} \;
This maybe works for you:
#!/bin/bash
DIR=/your/Folder1
DEST=/your/Folder2
for f in `ls -1 $DIR | grep .jpg | egrep -v ".+\-[0-9]{2,4}x[0-9]{2,4}\.jpg"`
do
f=$(basename $f)
F=$(echo "$f" | sed "s/[^A-Z|a-z|0-9|\.]//g;")
cp -p "$DIR/$f" "$DEST/$F"
done
You can use MV instead of CP if you needit.
EDITED
This will get only the files you have to copy:
ls -1 $DIR/*.jpg | egrep -v ".+\-[0-9]{2,4}x[0-9]{2,4}\.jpg
basename command get only the file name in order to replace weir characters and prepare to move
sed it's replacing all character if the aren't letters and numbers (and a dot for file extension)
Something like this perhaps?
for file in Folder1/*.jpg; do
case $file in
*-70x70.jpg | *-100x100.jpg) ;;
*) cp "$file" "Folder2/Image${file#Folder1/Image?}" ;;
esac
done
The construct ${variable#pattern} removes any match for pattern from the beginning of the value of $variable. The pattern Folder1/Image? matches the literal text Folder1/Image (we prepend back the static Image part then) and one arbitrary character.
If the offending character is not a single byte, try doubling the question mark for a start; that will match two arbitrary characters (or bytes, if your locale etc are configured that way). If you have a combining Unicode sequence, it takes much more than that, though -- a hex dump of the actual bytes used to represent the file name would be helpful for diagnosing this. Anyway, you can simply trim from the other end instead, although that gets a bit more involved;
*) base=${file#Folder1/}
prefix=${base%%[0-9]*}
cp "$file" "Folder2/Image${base#$prefix}" ;;
The variant ${variable%pattern} trims from the end instead of the beginning, and doubling the # or % causes the shell to trim the longest possible match instead of the shortest. (I believe the longest-possible matching is a Bash extension?)

Add prefix to all images (recursive)

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

How to loop over directories in Linux?

I am writing a script in bash on Linux and need to go through all subdirectory names in a given directory. How can I loop through these directories (and skip regular files)?
For example:
the given directory is /tmp/
it has the following subdirectories: /tmp/A, /tmp/B, /tmp/C
I want to retrieve A, B, C.
All answers so far use find, so here's one with just the shell. No need for external tools in your case:
for dir in /tmp/*/ # list directories in the form "/tmp/dirname/"
do
dir=${dir%*/} # remove the trailing "/"
echo "${dir##*/}" # print everything after the final "/"
done
cd /tmp
find . -maxdepth 1 -mindepth 1 -type d -printf '%f\n'
A short explanation:
find finds files (quite obviously)
. is the current directory, which after the cd is /tmp (IMHO this is more flexible than having /tmp directly in the find command. You have only one place, the cd, to change, if you want more actions to take place in this folder)
-maxdepth 1 and -mindepth 1 make sure that find only looks in the current directory and doesn't include . itself in the result
-type d looks only for directories
-printf '%f\n prints only the found folder's name (plus a newline) for each hit.
Et voilà!
You can loop through all directories including hidden directrories (beginning with a dot) with:
for file in */ .*/ ; do echo "$file is a directory"; done
note: using the list */ .*/ works in zsh only if there exist at least one hidden directory in the folder. In bash it will show also . and ..
Another possibility for bash to include hidden directories would be to use:
shopt -s dotglob;
for file in */ ; do echo "$file is a directory"; done
If you want to exclude symlinks:
for file in */ ; do
if [[ -d "$file" && ! -L "$file" ]]; then
echo "$file is a directory";
fi;
done
To output only the trailing directory name (A,B,C as questioned) in each solution use this within the loops:
file="${file%/}" # strip trailing slash
file="${file##*/}" # strip path and leading slash
echo "$file is the directoryname without slashes"
Example (this also works with directories which contains spaces):
mkdir /tmp/A /tmp/B /tmp/C "/tmp/ dir with spaces"
for file in /tmp/*/ ; do file="${file%/}"; echo "${file##*/}"; done
Works with directories which contains spaces
Inspired by Sorpigal
while IFS= read -d $'\0' -r file ; do
echo $file; ls $file ;
done < <(find /path/to/dir/ -mindepth 1 -maxdepth 1 -type d -print0)
Original post (Does not work with spaces)
Inspired by Boldewyn: Example of loop with find command.
for D in $(find /path/to/dir/ -mindepth 1 -maxdepth 1 -type d) ; do
echo $D ;
done
find . -mindepth 1 -maxdepth 1 -type d -printf "%P\n"
The technique I use most often is find | xargs. For example, if you want to make every file in this directory and all of its subdirectories world-readable, you can do:
find . -type f -print0 | xargs -0 chmod go+r
find . -type d -print0 | xargs -0 chmod go+rx
The -print0 option terminates with a NULL character instead of a space. The -0 option splits its input the same way. So this is the combination to use on files with spaces.
You can picture this chain of commands as taking every line output by find and sticking it on the end of a chmod command.
If the command you want to run as its argument in the middle instead of on the end, you have to be a bit creative. For instance, I needed to change into every subdirectory and run the command latemk -c. So I used (from Wikipedia):
find . -type d -depth 1 -print0 | \
xargs -0 sh -c 'for dir; do pushd "$dir" && latexmk -c && popd; done' fnord
This has the effect of for dir $(subdirs); do stuff; done, but is safe for directories with spaces in their names. Also, the separate calls to stuff are made in the same shell, which is why in my command we have to return back to the current directory with popd.
a minimal bash loop you can build off of (based off ghostdog74 answer)
for dir in directory/*
do
echo ${dir}
done
to zip a whole bunch of files by directory
for dir in directory/*
do
zip -r ${dir##*/} ${dir}
done
If you want to execute multiple commands in a for loop, you can save the result of find with mapfile (bash >= 4) as a variable and go through the array with ${dirlist[#]}. It also works with directories containing spaces.
The find command is based on the answer by Boldewyn. Further information about the find command can be found there.
IFS=""
mapfile -t dirlist < <( find . -maxdepth 1 -mindepth 1 -type d -printf '%f\n' )
for dir in ${dirlist[#]}; do
echo ">${dir}<"
# more commands can go here ...
done
TL;DR:
(cd /tmp; for d in */; do echo "${d%/}"; done)
Explanation.
There's no need to use external programs. What you need is a shell globbing pattern. To avoid the need of removing /tmp afterward, I'm running it in a subshell, which may or not be suitable for your purposes.
Shell globbing patterns in a nutshell:
* Match any non-empty string any number of times.
? Match exactly one character.
[...] Matches with a character from between the brackets. You can also specify ranges ([a-z], [A-F0-9], etc.) or classes ([:digit:], [:alpha:], etc.).
[^...] Match one of the characters not between the braces.
* If no file names match the pattern, the shell will return the pattern unchanged. Any character or string that is not one of the above represents itself.
Consequently, the pattern */ will match any file name that ends with a /. A trailing / in a file name unambiguously identifies a directory.
The last bit is removing the trailing slash, which is achieved with the variable substitution ${var%PATTERN}, which removes the shortest matching pattern from the end of the string contained in var, and where PATTERN is any valid globbing pattern. So we write ${d%/}, meaning we want to remove the trailing slash from the string represented by d.
find . -type d -maxdepth 1
In short, put the results of find into an array and iterate the array and do what you want. Not the quickest but more organized thinking.
#!/bin/bash
cd /tmp
declare -a results=(`find -type d`)
#Iterate the results
for path in ${results[#]}
do
echo "Your path is $path"
#Do something with the path..
if [[ $path =~ "/A" ]]; then
echo $path | awk -F / '{print $NF}'
#prints A
elif [[ $path =~ "/B" ]]; then
echo $path | awk -F / '{print $NF}'
#Prints B
elif [[ $path =~ "/C" ]]; then
echo $path | awk -F / '{print $NF}'
#Prints C
fi
done
This can be reduced to find -type d | grep "/A" | awk -F / '{print $NF}' prints A
find -type d | grep "/B" | awk -F / '{print $NF}' prints B
find -type d | grep "/C" | awk -F / '{print $NF}' prints C

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