Suppose we have the following command and its related output :
gsettings list-recursively org.gnome.Terminal.ProfilesList | head -n 1 | grep -oP '(?<=\[).*?(?=\])'
Output :
'b1dcc9dd-5262-4d8d-a863-c897e6d979b9', 'ca4b733c-53f2-4a7e-8a47-dce8de182546', '802e8bb8-1b78-4e1b-b97a-538d7e2f9c63', '892cd84f-9718-46ef-be06-eeda0a0550b1', '6a7d836f-b2e8-4a1e-87c9-e64e9692c8a8', '2b9e8848-0b4a-44c7-98c7-3a7e880e9b45', 'b23a4a62-3e25-40ae-844f-00fb1fc244d9'
I need to use gsettings command in a script and create filenames regarding to output ot gessetings command. For example a file name should be
b1dcc9dd-5262-4d8d-a863-c897e6d979b9
the next one :
ca4b733c-53f2-4a7e-8a47-dce8de182546
and so on.
How I can do this?
Another solution... just pipe the output of your command to:
your_command | sed "s/[ ']//g" | xargs -d, touch
You can use process substitution to read your gsettings output and store it in an array :
IFS=', ' read -r -a array < <(gsettings)
for f in "${array[#]}"
do
file=$(echo $f |tr -d "'" ) # removes leading and trailing quotes
touch "$file"
done
Related
I want to write a bash script and I need to get the filenames in a directory and I've done this :
list=`ls -p -m -1 $dir | grep -v /`
list=`echo $list | tr ' ' ','`
IFS=',' read -ra list_array <<< $list
If no file with whitespaces in the current directory exists , then the variable list_array holds the correct space-seperated array of filenames :
$ echo "${list_array[*]}"
a a.rar a.tar a.zip blah blah blah
But that wouldn't work correctly in situations where there exists some files with whitespaces in their names.To mitigate this , I changed that as follows :
list=`ls -p -m $dir | grep -v /` #This doesn't work in for filenames without whitespace
IFS=',' read -ra list_array <<< $list
But now list_array only holds the name of the first file.
Any help is greatly appreciated.
You can use newlines as IFS.
IFS=$'\n'
list_array=(`ls -p -m -1 . | grep -v /`)
In a bash script, I am trying to remove the directory name in filenames :
documents/file.txt
direc/file5.txt
file2.txt
file3.txt
So I try to first see if there is a "/" and if yes delete everything before :
for i in **/*.scss *.scss; do
echo "$i" | sed -n '^/.*\// s/^.*\///p'
done
But it doesn't work for files in the current directory, it gives me a blank string.
I get :
file.txt
file5.txt
When you only want the filename, use basename instead of sed.
# basename /path/to/file
returns file
here is the man page
Your sed attempt is basically fine, but you should print regardless of whether you performed a substitution; take out the -n and the p at the end. (Also there was an unrelated syntax error.)
Also, don't needlessly loop over all files.
printf '%s\n' **/*.scss *.scss |
sed -n 's%^.*/%%p'
This also can be done with awk bash util.
Example:
echo "1/2/i.py" | awk 'BEGIN {FS="/"} {print $NF}'
output: i.py
Eventually, I did :
for i in **/*.scss *.scss; do
# for i in *.scss; do
# for i in _hm-globals.scss; do
name=${i##*/} # remove dir name
name=${name%.scss} # remove extension
name=`echo "$name" | sed -n "s/^_hm-//p"` # remove _hm-
if [[ $name = *"."* ]]; then
name=`echo "$name" | sed -n 's/\./-/p'` #replace . to --
fi
echo "$name" >&2
done
I have file with a few lines:
x 1
y 2
z 3 t
I need to pass each line as paramater to some program:
$ program "x 1" "y 2" "z 3 t"
I know how to do it with two commands:
$ readarray -t a < file
$ program "${a[#]}"
How can i do it with one command? Something like that:
$ program ??? file ???
The (default) options of your readarray command indicate that your file items are separated by newlines.
So in order to achieve what you want in one command, you can take advantage of the special IFS variable to use word splitting w.r.t. newlines (see e.g. this doc) and call your program with a non-quoted command substitution:
IFS=$'\n'; program $(cat file)
As suggested by #CharlesDuffy:
you may want to disable globbing by running beforehand set -f, and if you want to keep these modifications local, you can enclose the whole in a subshell:
( set -f; IFS=$'\n'; program $(cat file) )
to avoid the performance penalty of the parens and of the /bin/cat process, you can write instead:
( set -f; IFS=$'\n'; exec program $(<file) )
where $(<file) is a Bash equivalent to to $(cat file) (faster as it doesn't require forking /bin/cat), and exec consumes the subshell created by the parens.
However, note that the exec trick won't work and should be removed if program is not a real program in the PATH (that is, you'll get exec: program: not found if program is just a function defined in your script).
Passing a set of params should be more organized :
In this example case I'm looking for a file containing chk_disk_issue=something etc.. so I set the values by reading a config file which I pass in as a param.
# -- read specific variables from the config file (if found) --
if [ -f "${file}" ] ;then
while IFS= read -r line ;do
if ! [[ $line = *"#"* ]]; then
var="$(echo $line | cut -d'=' -f1)"
case "$var" in
chk_disk_issue)
chk_disk_issue="$(echo $line | tr -d '[:space:]' | cut -d'=' -f2 | sed 's/[^0-9]*//g')"
;;
chk_mem_issue)
chk_mem_issue="$(echo $line | tr -d '[:space:]' | cut -d'=' -f2 | sed 's/[^0-9]*//g')"
;;
chk_cpu_issue)
chk_cpu_issue="$(echo $line | tr -d '[:space:]' | cut -d'=' -f2 | sed 's/[^0-9]*//g')"
;;
esac
fi
done < "${file}"
fi
if these are not params then find a way for your script to read them as data inside of the script and pass in the file name.
I have piped the output of ls command into a file. The contents are like so:
[Chihiro]_Grisaia_no_Kajitsu_-_01_[1920x816_Blu-ray_FLAC][D2B961D6].mkv
[Chihiro]_Grisaia_no_Kajitsu_-_02_[1920x816_Blu-ray_FLAC][38F88A81].mkv
[Chihiro]_Grisaia_no_Kajitsu_-_03_[1920x816_Blu-ray_FLAC][410F74F7].mkv
My attempt to rename these episodes according to episode number is as follows:
cat grisaia | while read line;
#get the episode number
do EP=$(echo $line | egrep -o "_([0-9]{2})_" | cut -d "_" -f2)
if [[ $EP ]]
#escape special characters
then line=$(echo $line | sed 's/\[/\\[/g' | sed 's/\]/\\]/g')
mv "$line" "Grisaia_no_Kajitsu_${EP}.mkv"
fi
done
The mv commands exit with code 1 with the following error:
mv: cannot stat
'\[Chihiro\]_Grisaia_no_Kajitsu_-01\[1920x816_Blu-ray_FLAC\]\[D2B961D6\].mkv':
No such file or directory
What I really don't get is that if I copy the file that could not be stat and attempt to stat the file, it works. I can even take the exact same string that is output and execute the mv command individually.
If you surround your variable ($line) with double quotes (") you don't need to escape those special characters. So you have two options there:
Remove the following assignation completely:
then # line=$(echo $line | sed 's/\[/\\[/g' | sed 's/\]/\\]/g')`
or
Remove the double quotes in the following line:
mv $line "Grisaia_no_Kajitsu_${EP}.mkv"
Further considerations
Parsing the output of ls is never a good idea. Think about filenames with spaces. See this document for more information.
The cat here is unnecessary:
cat grisaia | while read line;
...
done
Use this instead to avoid an unnecessary pipe:
while read line;
...
done < grisaia
Why is good to avoid pipes in some scenarios? (answering comment)
Pipes create subshells (which are expensive), and you can also make some mistakes as the following:
last=""
cat grisaia | while read line; do
last=$line
done
echo $last # surprise!! it outputs an empty string
The reason is that $last inside the loop belongs to another subshell.
Now, see the same approach wothout pipes:
while read line; do
last=$line
done < grisaia
echo $last # it works as expected and prints the last line
I am writing a bash script where i will need to check a directory for existing files and look at the last 4 digits of the first segment of the file name to set the counter when adding new files to the directory.
Naming Scructure:
yymmddHNAZXLCOM0001.835
I need to put the portion in the example 0001 into a CTR variable so the next file it puts into the directory will be
yymmddHNAZXLCOM0002.835
and so on.
what would be the easiest and shortest way to do this?
You can do this with sed:
filename="yymmddHNAZXLCOM0001.835"
first_part=$(echo $filename | sed -e 's/\(.*\)\([0-9]\{4,4\}\)\.\(.*\)/\1/')
counter=$(echo $filename | sed -e 's/\(.*\)\([0-9]\{4,4\}\)\.\(.*\)/\2/')
suffix=$(echo $filename | sed -e 's/\(.*\)\([0-9]\{4,4\}\)\.\(.*\)/\3/')
echo "$first_part$(printf "%04u" $(($counter + 1))).$suffix"
=> "yymmddHNAZXLCOM0002.835"
All three sed calls use the same regular expression. The only thing that changes is the group selected to return. There's probably a way to do all of that in one call, but my sed-fu is rusty.
Alternate version, using a Bash array:
filename="yymmddHNAZXLCOM0001.835"
ary=($(echo $filename | sed -e 's/\(.*\)\([0-9]\{4,4\}\)\.\(.*\)/\1 \2 \3/'))
echo "${ary[0]}$(printf "%04u" $((${ary[1]} + 1))).${ary[2]}"
=> "yymmddHNAZXLCOM0002.835"
Note: This version assumes that the filename does not have spaces in it.
Try this...
current=`echo yymmddHNAZXLCOM0001.835 | cut -d . -f 1 | rev | cut -c 1-4 | rev`
next=`echo $current | awk '{printf("%04i",$0+1)}'`
f() {
if [[ $1 =~ (.*)([[:digit:]]{4})(\.[^.]*)$ ]]; then
local -a ctr=("${BASH_REMATCH[#]:1}")
touch "${ctr}$((++ctr[1]))${ctr[2]}"
# ...
else
echo 'no matches'
fi
}
shopt -s nullglob
f *