Useful Unix/Linux bash functions
For day to day hacker, they may be more elegant ways to do it (PERL, AWK), but they have work well for me.
- Upper case file name or variable,
- Search and replace in all files content recursively,
- Renaming all files recursively,
- Renaming all directory recursively,
- Copying a set of files from one directory to the other and preserving hierarchy.
Upper case file name or variable
function toUpper {
echo "$1" | sed ‘y/abcdefghijklmnopqrstuvwxyz/ABCDEFGHIJKLMNOPQRSTUVWXYZ/’
# or
# echo "$1" | tr -s ‘[:lower:]’ ‘[:upper:]’
}Usage:
- in a script toUpper “cedric”
- assign to a variable in a script result=$(toUpper $variable) or result=$(toUpper “cedric”)
Search and replace in all files content recursively
This can go through all directories
- $3 as base directory
- Search for $1
- Replace with $2
function searchAndReplaceRecursively {
echo "replace ‘$1’ with ‘$2’ in dir ‘$3’";
for file in `find $3 -type f`;
do
echo -ne ".";
sed -e ‘s/’$1’/’$2’/g’ $file > /tmp/tempfile.tmp
mv /tmp/tempfile.tmp $file
done
echo "";
}Usage:
- in a script searchAndReplaceRecursively “cedric” “unix” .
Renaming all files recursively
This can go through all directories, renaming all files based on parameters:
- $3 as base directory,
- Search for $1 in filename,
- Replace with $2 in filename.
function renameFilenameRecursively {
for file in `find $3 -type f`;
do
newFilename=`basename $file | sed -e ‘s/’$1’/’$2’/g’`;
dirs=`dirname $file`;
mv $file $dirs/$newFilename;
done
}Usage:
- in a script renameFilenameRecursively “cedric” “unix” .
Renaming all directory recursively
This can go through all directories, renaming all directories based on parameters:
- $3 as base directory
- Search for $1 in directory name
- Replace with $2 in directory name
- in bold, you can put either
- *$1 the pattern has to be at end of directory name,
- $1* the pattern has to be at beginning of directory name,
- *$1* the pattern has to be in the middle of directory name,
- remove the case all together, the grep $1 filter already the result of the command find.
function renameDirectoriesRecursively {
for adir in `find $3 -type d | grep $1`;
do
case $adir in
*$1* )
newdirname=$( echo "$adir" | sed -e ‘s/’$1’/’$2’/g’ );
echo Found $adir will be renamed to $newdirname;
mv $adir $newDirName;
esac
done
}Usage:
- in a script renameDirectoriesRecursively “cedric” “unix” .
Copying a set of files from one directory to the other and preserving hierarchy
find . -name $1 -exec cp -r --parents {} $destination \;
