Renaming part of a filename [duplicate] - bash

This question already has answers here:
Rename multiple files based on pattern in Unix
(24 answers)
Closed 5 years ago.
I have loads of files which look like this:
DET01-ABC-5_50-001.dat
...
DET01-ABC-5_50-0025.dat
and I want them to look like this:
DET01-XYZ-5_50-001.dat
...
DET01-XYZ-5_50-0025.dat
How can I do this?

There are a couple of variants of a rename command, in your case, it may be as simple as
rename ABC XYZ *.dat
You may have a version which takes a Perl regex;
rename 's/ABC/XYZ/' *.dat

for file in *.dat ; do mv $file ${file//ABC/XYZ} ; done
No rename or sed needed. Just bash parameter expansion.

Something like this will do it. The for loop may need to be modified depending on which filenames you wish to capture.
for fspec1 in DET01-ABC-5_50-*.dat ; do
fspec2=$(echo ${fspec1} | sed 's/-ABC-/-XYZ-/')
mv ${fspec1} ${fspec2}
done
You should always test these scripts on copies of your data, by the way, and in totally different directories.

You'll need to learn how to use sed http://unixhelp.ed.ac.uk/CGI/man-cgi?sed
And also to use for so you can loop through your file entries http://www.cyberciti.biz/faq/bash-for-loop/
Your command will look something like this, I don't have a term beside me so I can't check
for i in `dir` do mv $i `echo $i | sed '/orig/new/g'`

I like to do this with sed. In you case:
for x in DET01-*.dat; do
echo $x | sed -r 's/DET01-ABC-(.+)\.dat/mv -v "\0" "DET01-XYZ-\1.dat"/'
done | sh -e
It is best to omit the "sh -e" part first to see what will be executed.

All of these answers are simple and good. However, I always like to add an interactive mode to these scripts so that I can find false positives.
if [[ -n $inInteractiveMode ]]
then
echo -e -n "$oldFileName => $newFileName\nDo you want to do this change? [Y/n]: "
read run
[[ -z $run || "$run" == "y" || "$run" == "Y" ]] && mv "$oldFileName" "$newFileName"
fi
Or make interactive mode the default and add a force flag (-f | --force) for automated scripts or if you're feeling daring. And this doesn't slow you down too much: the default response is "yes, I do want to rename" so you can just hit the enter key at each prompt (because of the -z $run test.

Related

Delete duplicate commands of zsh_history keeping last occurence

I'm trying to write a shell script that deletes duplicate commands from my zsh_history file. Having no real shell script experience and given my C background I wrote this monstrosity that seems to work (only on Mac though), but takes a couple of lifetimes to end:
#!/bin/sh
history=./.zsh_history
currentLines=$(grep -c '^' $history)
wordToBeSearched=""
currentWord=""
contrastor=0
searchdex=""
echo "Currently handling a grand total of: $currentLines lines. Please stand by..."
while (( $currentLines - $contrastor > 0 ))
do
searchdex=1
wordToBeSearched=$(awk "NR==$currentLines - $contrastor" $history | cut -d ";" -f 2)
echo "$wordToBeSearched A BUSCAR"
while (( $currentLines - $contrastor - $searchdex > 0 ))
do
currentWord=$(awk "NR==$currentLines - $contrastor - $searchdex" $history | cut -d ";" -f 2)
echo $currentWord
if test "$currentWord" == "$wordToBeSearched"
then
sed -i .bak "$((currentLines - $contrastor - $searchdex)) d" $history
currentLines=$(grep -c '^' $history)
echo "Line deleted. New number of lines: $currentLines"
let "searchdex--"
fi
let "searchdex++"
done
let "contrastor++"
done
^THIS IS HORRIBLE CODE NOONE SHOULD USE^
I'm now looking for a less life-consuming approach using more shell-like conventions, mainly sed at this point. Thing is, zsh_history stores commands in a very specific way:
: 1652789298:0;man sed
Where the command itself is always preceded by ":0;".
I'd like to find a way to delete duplicate commands while keeping the last occurrence of each command intact and in order.
Currently I'm at a point where I have a functional line that will delete strange lines that find their way into the file (newlines and such):
#sed -i '/^:/!d' $history
But that's about it. Not really sure how get the expression to look for into a sed without falling back into everlasting whiles or how to delete the duplicates while keeping the last-occurring command.
The zsh option hist_ignore_all_dups should do what you want. Just add setopt hist_ignore_all_dups to your zshrc.
I wanted something similar, but I dont care about preserving the last one as you mentioned. This is just finding duplicates and removing them.
I used this command and then removed my .zsh_history and replacing it with the .zhistory that this command outputs
So from your home folder:
cat -n .zsh_history | sort -t ';' -uk2 | sort -nk1 | cut -f2- > .zhistory
This effectively will give you the file .zhistory containing the changed list, in my case it went from 9000 lines to 3000, you can check it with wc -l .zhistory to count the number of lines it has.
Please double check and make a backup of your zsh history before doing anything with it.
The sort command might be able to be modified to sort it by numerical value and somehow archieve what you want, but you will have to investigate further about that.
I found the script here, along with some commands to avoid saving duplicates in the future
I didn't want to rename the history file.
# dedupe_lines.zsh
if [ $# -eq 0 ]; then
echo "Error: No file specified" >&2
exit 1
fi
if [ ! -f $1 ]; then
echo "Error: File not found" >&2
exit 1
fi
sort $1 | uniq >temp.txt
mv temp.txt $1
Add dedupe_lines.zsh to your home directory, then make it executable.
chmod +x dedupe_lines.zsh
Run it.
./dedupe_lines.zsh .zsh_history

Adding test_ in front of a file name with path

I have a list of files stored in a text file, and if a Python file is found in that list. I want to the corresponding test file using Pytest.
My file looks like this:
/folder1/file1.txt
/folder1/file2.jpg
/folder1/file3.md
/folder1/file4.py
/folder1/folder2/file5.py
When 4th/5th files are found, I want to run the command pytest like:
pytest /folder1/test_file4.py
pytest /folder1/folder2/test_file5.py
Currently, I am using this command:
cat /workspace/filelist.txt | while read line; do if [[ $$line == *.py ]]; then exec "pytest test_$${line}"; fi; done;
which is not working correctly, as I have file path in the text as well. Any idea how to implement this?
Using Bash's variable substring removal to add the test_. One-liner:
$ while read line; do if [[ $line == *.py ]]; then echo "pytest ${line%/*}/test_${line##*/}"; fi; done < file
In more readable form:
while read line
do
if [[ $line == *.py ]]
then
echo "pytest ${line%/*}/test_${line##*/}"
fi
done < file
Output:
pytest /folder1/test_file4.py
pytest /folder1/folder2/test_file5.py
Don't know anything about the Google Cloudbuild so I'll let you experiment with the double dollar signs.
Update:
In case there are files already with test_ prefix, use this bash script that utilizes extglob in variable substring removal:
shopt -s extglob # notice
while read line
do
if [[ $line == *.py ]]
then
echo "pytest ${line%/*}/test_${line##*/?(test_)}" # notice
fi
done < file
You can easily refactor all your conditions into a simple sed script. This also gets rid of the useless cat and the similarly useless exec.
sed -n 's%[^/]*\.py$%test_&%p' /workspace/filelist.txt |
xargs -n 1 pytest
The regular expression matches anything after the last slash, which means the entire line if there is no slash; we include the .py suffix to make sure this only matches those files.
The pipe to xargs is a common way to convert standard input into command-line arguments. The -n 1 says to pass one argument at a time, rather than as many as possible. (Maybe pytest allows you to specify many tests; then, you can take out the -n 1 and let xargs pass in as many as it can fit.)
If you want to avoid adding the test_ prefix to files which already have it, one solution is to break up the sed script into two separate actions:
sed -n '/test_[^/]*\.py/p;t;s%[^/]*\.py$%test_&%p' /workspace/filelist.txt |
xargs -n 1 pytest
The first p simply prints the matches verbatim; the t says if that matched, skip the rest of the script for this input.
(MacOS / BSD sed will want a newline instead of a semicolon after the t command.)
sed is arguably a bit of a read-only language; this is already pressing towards the boundary where perhaps you would rewrite this in Awk instead.
You may want to focus on lines that ends with ".py" string
You can achieve that using grep combined with a regex so you can figure out if a line ends with .py - that eliminates the if statement.
IFS=$'\n'
for file in $(cat /workspace/filelist.txt|grep '\.py$');do pytest $file;done

bash script rename multiple files [duplicate]

This question already has answers here:
Rename filename to another name
(3 answers)
Closed 7 years ago.
Let´s say I have a bunch of files named something like this: bsdsa120226.nai bdeqa140223.nai and I want to rename them to 120226.nai 140223.nai. How can i achieve this using the script below?
#!/bin/bash
name1=`ls *nai*`
names=`ls *nai*| grep -Po '(?<=.{5}).+'`
for i in $name1
do
for y in $names
do
mv $i $y
done
done
Solution:
name1=`ls *nai*`
for i in $name1
do
y=$(echo "$i" | grep -Po '(?<=.{5}).+')
mv $i $y
done
This:
#!/bin/bash
shopt -s extglob nullglob
for file in *+([[:digit:]]).nai; do
echo mv -nv -- "$file" "${file##+([^[:digit:]])}"
done
Remove the echo if you're happy with the mv commands.
Note. This solution does not assume that there are 5 leading characters to delete. It will delete all the leading non-numeric characters.
Using only bash, you could do this:
for file in *nai* ; do
echo mv -- "$file" "${file:5}"
done
(Remove the echo when satisfied with the output.)
Avoid ls in scripts, except for displaying information. Use plain globbing instead.
See also How do I do string manipulations in bash? for more string manipulation techniques.
Your script can't work with that structure: if you have 5 files, it will call mv five times for the first file (once for each element in the second list), five times for the second, etc. You'd need to iterate over the two sets of names in lockstep. (It also doesn't deal with things like whitespace in filenames.)
You would be better off using rename (prename on some systems) since that allows you to use Perl regular expressions to do the renaming, along the lines of:
prename 's/^.{5}//' *.nai
The reason your script is not behaving is that, for every source file, you're attempting to rename it to every target file.
If you need to limit yourself to using that script, you need to work out the single target file for each source file, something like:
#!/bin/bash
for i in *.nai; do
y=$(echo "$i" | cut -c6-)
mv "$i" "$y"
done
If your system has rename tool, it's better to go with the simple rename command,
rename 's/^.{5}//' *.nai
It just remove the first 5 characters from the file name.
OR
for i in *.nai; do mv "$i" $(grep -oP '(?<=^.{5}).+' <<< "$i"); done

Performance with bash loop when renaming files

Sometimes I need to rename some amount of files, such as add a prefix or remove something.
At first I wrote a python script. It works well, and I want a shell version. Therefore I wrote something like that:
$1 - which directory to list,
$2 - what pattern will be replacement,
$3 - replacement.
echo "usage: dir pattern replacement"
for fname in `ls $1`
do
newName=$(echo $fname | sed "s/^$2/$3/")
echo 'mv' "$1/$fname" "$1/$newName&&"
mv "$1/$fname" "$1/$newName"
done
It works but very slowly, probably because it needs to create a process (here sed and mv) and destroy it and create same process again just to have a different argument. Is that true? If so, how to avoid it, how can I get a faster version?
I thought to offer all processed files a name (using sed to process them at once), but it still needs mv in the loop.
Please tell me, how you guys do it? Thanks. If you find my question hard to understand please be patient, my English is not very good, sorry.
--- update ---
I am sorry for my description. My core question is: "IF we should use some command in loop, will that lower performance?" Because in for i in {1..100000}; do ls 1>/dev/null; done creating and destroying a process will take most of the time. So what I want is "Is there any way to reduce that cost?".
Thanks to kev and S.R.I for giving me a rename solution to rename files.
Every time you call an external binary (ls, sed, mv), bash has to fork itself to exec the command and that takes a big performance hit.
You can do everything you want to do in pure bash 4.X and only need to call mv
pat_rename(){
if [[ ! -d "$1" ]]; then
echo "Error: '$1' is not a valid directory"
return
fi
shopt -s globstar
cd "$1"
for file in **; do
echo "mv $file ${file//$2/$3}"
done
}
Simplest first. What's wrong with rename?
mkdir tstbin
for i in `seq 1 20`
do
touch tstbin/filename$i.txt
done
rename .txt .html tstbin/*.txt
Or are you using an older *nix machine?
To avoid re-executing sed on each file, you could instead setup two name streams, one original, and one transformed, then sip from the ends:
exec 3< <(ls)
exec 4< <(ls | sed 's/from/to/')
IFS=`echo`
while read -u3 orig && read -u4 to; do
mv "${orig}" "${to}";
done;
I think you can store all of file names into a file or string, and use awk and sed do it once instead of one by one.

In a small script to monitor a folder for new files, the script seems to be finding the wrong files

I'm using this script to monitor the downloads folder for new .bin files being created. However, it doesn't seem to be working. If I remove the grep, I can make it copy any file created in the Downloads folder, but with the grep it's not working. I suspect the problem is how I'm trying to compare the two values, but I'm really not sure what to do.
#!/bin/sh
downloadDir="$HOME/Downloads/"
mbedDir="/media/mbed"
inotifywait -m --format %f -e create $downloadDir -q | \
while read line; do
if [ $(ls $downloadDir -a1 | grep '[^.].*bin' | head -1) == $line ]; then
cp "$downloadDir/$line" "$mbedDir/$line"
fi
done
The ls $downloadDir -a1 | grep '[^.].*bin' | head -1 is the wrong way to go about this. To see why, suppose you had files named a.txt and b.bin in the download directory, and then c.bin was added. inotifywait would print c.bin, ls would print a.txt\nb.bin\nc.bin (with actual newlines, not \n), grep would thin that to b.bin\nc.bin, head would remove all but the first line leaving b.bin, which would not match c.bin. You need to be checking $line to see if it ends in .bin, not scanning a directory listing. I'll give you three ways to do this:
First option, use grep to check $line, not the listing:
if echo "$line" | grep -q '[.]bin$'; then
Note that I'm using the -q option to supress grep's output, and instead simply letting the if command check its exit status (success if it found a match, failure if not). Also, the RE is anchored to the end of the line, and the period is in brackets so it'll only match an actual period (normally, . in a regular expression matches any single character). \.bin$ would also work here.
Second option, use the shell's ability to edit variable contents to see if $line ends in .bin:
if [ "${line%.bin}" != "$line" ]; then
the "${line%.bin}" part gives the value of $line with .bin trimmed from the end if it's there. If that's not the same as $line itself, then $line must've ended with .bin.
Third option, use bash's [[ ]] expression to do pattern matching directly:
if [[ "$line" == *.bin ]]; then
This is (IMHO) the simplest and clearest of the bunch, but it only works in bash (i.e. you must start the script with #!/bin/bash).
Other notes: to avoid some possible issues with whitespace and backslashes in filenames, use while IFS= read -r line; do and follow #shellter's recommendation about double-quotes religiously.
Also, I'm not very familiar with inotifywait, but AIUI its -e create option will notify you when the file is created, not when its contents are fully written out. Depending on the timing, you may wind up copying partially-written files.
Finally, you don't have any checking for duplicate filenames. What should happen if you download a file named foo.bin, it gets copied, you delete the original, then download a different file named foo.bin. As the script is now, it'll silently overwrite the first foo.bin. If this isn't what you want, you should add something like:
if [ ! -e "$mbedDir/$line" ]; then
cp "$downloadDir/$line" "$mbedDir/$line"
elif ! cmp -s "$downloadDir/$line" "$mbedDir/$line"; then
echo "Eeek, a duplicate filename!" >&2
# or possibly something more constructive than that...
fi

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