Bash scripting : How do I rename files to remove numeric characters at the beginning? - linux

mv command doesnt accept pattern matching like grep !
Whats the good way to handle this and similar kind of operations ?

There's the rename tool, but if that's not what you want, you can do:
for file in *; do
new_file="${file##[0-9]}" # Strip all leading numbers
mv "$file" "$newfile"
done

Related

mv renaming filename to _*_

Given an example that my file name is
A_BC_DEF_GH_IJ_LMNO_PQ_11111111_1111111111_111111_AB.dat.meta
i am trying to rename this with unix command but when i tried using this cmd
for f in *.meta; do mv "$f" "$(echo $f|sed s/[0-9]/?/g|sed 's/-/*/g')" ; done
my file is renamed to
A_BC_DEF_GH_IJ_LMNO_PQ_????????_????????????????????_???????_AB.dat.meta
it is expected to rename the file to
A_BC_DEF_GH_IJ_LMNO_PQ__????????_????????????????????_*_AB.dat.meta
Im quite new with unix cmd , any approach that i should try ?
Since [0-9] and ? are undergoing filename expansion, you should quote them to avoid nasty error messages. With this in mind, I did a
echo A_BC_DEF_GH_IJ_LMNO_PQ_11111111_1111111111_111111_AB.dat.meta | sed 's/[0-9]/?/g'|sed 's/-/*/g'
and got as output A_BC_DEF_GH_IJ_LMNO_PQ????????????????????????AB.dat.meta, which makes sense to me. Why would you expect an asterisk in the resulting filename? In your second sed command, you are turning the hyphens into asterisks, but there is no hyphen in the input.
Of course it is pretty unsane to use question marks and asterisks in a file name, as this is just begging for trouble, but there is no law that you must not do this.
A_BC_DEF_GH_IJ_LMNO_PQ_11111111_1111111111_111111_AB.dat.meta
Match it with a regex. Remember which characters need to be escaped in sed. Remember about proper quoting - if you write $ it should be inside ". Note that if there are no files named *.meta it will just iterate over a string *.meta unless nullglob is set.
$ touch A_BC_DEF_GH_IJ_LMNO_PQ_11111111_1111111111_111111_AB.dat.meta
$ for f in *.meta; do mv "$f" "$(echo "$f" | sed 's/[0-9]/?/g; s/_\(?*\)_\(?*\)_\(?*\)_\([^_]*\)$/__\1_\2_*_\4/')" ; done

Linux renaming now.jpg.1 to spy_1.html

I want to use linux to rename 10 files.
now.jpg to spy_.html
And the other 9 should be
now.jpg.1 to spy_html.1
now.jpg.2 to spy_html.2
And so forth.
So far I have come up with this:
for f in *.jpg
do
mv “$f” “(“%s”%p”%i”%o”%n”%_).html”
done
But it doesn't work. Any tips appreciated.
You could use regular expression to capture the optional numeric extension and add it to the target file name. This should work with bash:
for f in *.jpg*
do
if [[ $f =~ now\.jpg(\.[0-9])? ]]; then
mv "$f" "spy.html${BASH_REMATCH[1]}"
fi
done
assuming you want spy.html[.#]. If you want an underscore for the files with the numerical extension, i.e. spy_html.1, it would be easier to issue two commands, one for now.jpg and one loop for the now.jpg.*.

linux rename files in bulk using bash script or command line one liner

I have a list of for example 100 files with the naming convention
<date>_<Time>_XYZ.xml.abc
<date>_<Time>_XYZ.xml
<date>_<Time>_XYZ.csv
for example
20140730_025373_XYZ.xml
20140730_015233_XYZ.xml.ab
20140730_015233_XYZ.csv
Now I want to write script which will remove anything between two underscores. for example in the above case
remove 015233 and change 20140730_015233_XYZ.xml.ab to 20140730_XYZ.xml.ab
remove 015233 and change 20140730_015233_XYZ.csv to 20140730_XYZ.csv
I have tried number of various options using rename, cut, mv but I am getting varied results, not the one which I expect.
You could use rename command if you want to rename files present inside the current directory,
rename 's/^([^_]*)_[^_]*(_.*)$/$1$2/g' *
You can use sed:
sed 's/\([^_]*\)_.*_\(.*\)/\1_\2/' files.list
You can also use cut command
cut -d'_' -f1,3 filename
for FILE in *; do mv "$FILE" "${FILE/_*_/_}"; done
And more specific is
for FILE in *.xml *.xml.ab *.csv; do mv "$FILE" "${FILE/_*_/_}"; done
Further:
for FILE in *_*_*.xml *_*_*.xml.ab *_*_*.csv; do mv "$FILE" "${FILE/_*_/_}"; done

Partial File Rename with different file types

Sorry if this is very simple compared to usual questions but I am just starting out. I have some files all with the same start name but of different file types, e.g:
1234.x
1234.y
1234.z
1234_V2.x
1234_V2.y
1234_V2.z
I want to rename the first part of these whilst keeping any ending and file type, e.g:
4321.x
4321.y
4321.z
4321_V2.x etc
I have tried using
mv 1234* 4321*
and
rename 1234* 4321*
But no luck! I have also been through all the other SO articles and although I could use a loop, most depend on the file type being the same.
Thanks in advance
You can use bash substitution:
for file in 1234*
do mv "$file" "4321${file#1234}"
done
OR, replace the do mv with the following
do mv "$file" "${file/1234/4321}"
See more in man bash under EXPANSION section, sub-section Parameter Expansion
Assuming your filenames for 1234 and 4321 i.e constant for all files, you can try this
for fn in `find . -name 1234*`
do
newf=`echo $fn | sed s/1234/4321/`
mv $fn $newfn
done
You can use a shell script, but it's kind of ugly because it will fork a lot, and thus, if you have a lot of files to rename, it will take time.
for f in 1234*; do echo mv $f $(echo $f | sed -e 's/1234/4321/'); done
Otherwize, rename is a good way to do it:
rename 's/1234/4321/' 1234*
Rename expects a regular expression as first parameter, see online documentation
See if it works:
rename "s/1234/4321/" 1234*
command means substitute(because of s) occurances of "1234" with "4321" in files that has name of pattern 1234*
You can also look at here. It is slightly more complicated than your case.

How to remove the extension of a file?

I have a folder that is full of .bak files and some other files also. I need to remove the extension of all .bak files in that folder. How do I make a command which will accept a folder name and then remove the extension of all .bak files in that folder ?
Thanks.
To remove a string from the end of a BASH variable, use the ${var%ending} syntax. It's one of a number of string manipulations available to you in BASH.
Use it like this:
# Run in the same directory as the files
for FILENAME in *.bak; do mv "$FILENAME" "${FILENAME%.bak}"; done
That works nicely as a one-liner, but you could also wrap it as a script to work in an arbitrary directory:
# If we're passed a parameter, cd into that directory. Otherwise, do nothing.
if [ -n "$1" ]; then
cd "$1"
fi
for FILENAME in *.bak; do mv "$FILENAME" "${FILENAME%.bak}"; done
Note that while quoting your variables is almost always a good practice, the for FILENAME in *.bak is still dangerous if any of your filenames might contain spaces. Read David W.'s answer for a more-robust solution, and this document for alternative solutions.
There are several ways to remove file suffixes:
In BASH and Kornshell, you can use the environment variable filtering. Search for ${parameter%word} in the BASH manpage for complete information. Basically, # is a left filter and % is a right filter. You can remember this because # is to the left of %.
If you use a double filter (i.e. ## or %%, you are trying to filter on the biggest match. If you have a single filter (i.e. # or %, you are trying to filter on the smallest match.
What matches is filtered out and you get the rest of the string:
file="this/is/my/file/name.txt"
echo ${file#*/} #Matches is "this/` and will print out "is/my/file/name.txt"
echo ${file##*/} #Matches "this/is/my/file/" and will print out "name.txt"
echo ${file%/*} #Matches "/name.txt" and will print out "/this/is/my/file"
echo ${file%%/*} #Matches "/is/my/file/name.txt" and will print out "this"
Notice this is a glob match and not a regular expression match!. If you want to remove a file suffix:
file_sans_ext=${file%.*}
The .* will match on the period and all characters after it. Since it is a single %, it will match on the smallest glob on the right side of the string. If the filter can't match anything, it the same as your original string.
You can verify a file suffix with something like this:
if [ "${file}" != "${file%.bak}" ]
then
echo "$file is a type '.bak' file"
else
echo "$file is not a type '.bak' file"
fi
Or you could do this:
file_suffix=$(file##*.}
echo "My file is a file '.$file_suffix'"
Note that this will remove the period of the file extension.
Next, we will loop:
find . -name "*.bak" -print0 | while read -d $'\0' file
do
echo "mv '$file' '${file%.bak}'"
done | tee find.out
The find command finds the files you specify. The -print0 separates out the names of the files with a NUL symbol -- which is one of the few characters not allowed in a file name. The -d $\0means that your input separators are NUL symbols. See how nicely thefind -print0andread -d $'\0'` together?
You should almost never use the for file in $(*.bak) method. This will fail if the files have any white space in the name.
Notice that this command doesn't actually move any files. Instead, it produces a find.out file with a list of all the file renames. You should always do something like this when you do commands that operate on massive amounts of files just to be sure everything is fine.
Once you've determined that all the commands in find.out are correct, you can run it like a shell script:
$ bash find.out
rename .bak '' *.bak
(rename is in the util-linux package)
Caveat: there is no error checking:
#!/bin/bash
cd "$1"
for i in *.bak ; do mv -f "$i" "${i%%.bak}" ; done
You can always use the find command to get all the subdirectories
for FILENAME in `find . -name "*.bak"`; do mv --force "$FILENAME" "${FILENAME%.bak}"; done

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