I need to output an array to a file in the following format.
File: a.txt
b.txt
I tried doing the following :
declare -a files=("a.txt" "b.txt")
empty=""
printf "File:" >> files.txt
for i in "${files[#]}"
do
printf "%-7s %-30s \n" "$empty" "$i" >> files.txt
done
But, I get the output as
File: a.txt
b.txt
Can anyone please help me to get the output in the required format.
#!/bin/bash
files=( 'a.txt' 'b.txt' 'c.txt' 'd.txt' )
set -- "${files[#]}"
printf 'File: %s\n' "$1"
shift
printf ' %s\n' "$#"
Output:
File: a.txt
b.txt
c.txt
d.txt
This uses the fact that printf will reuse its formatting string for all its other command line parameters.
We set the positional parameters to the list and then output the first element with the File: string prepended. We then shift $1 off the list of positional parameters and print the rest with a spacer string inserted.
Using sed
#!/bin/bash
declare -a files=("a.txt" "b.txt")
for i in "${files[#]}"
do
echo "$i" >> files.txt
done
sed -i '1 s/^/File: /' files.txt
sed -i '1 ! s/^/ /' files.txt
If you are using Mac, you have to modify sed commands in this way
sed -i '' '1 s/^/File: /' files.txt
sed -i '' '1 ! s/^/ /' files.txt
The output will be:
File: a.txt
b.txt
First of all we put into txt file all the file names (for loop). After that, via first sed command we add File: to the first line and via second sed command we add to all lines, except the first, six spaces equal to length of string File:
You could always started with a variable containing File: for the first iteration, and overwrite it with the correct number of spaces each time. The repeated assignment won't induce too much overhead.
prefix="File:"
for i in "${files[#]}"
do
printf "%-7s %-30s \n" "$prefix" "$i"
prefix=
done > Files.txt
Related
I have a test.txt file with the following contents
100001
100003
100007
100008
100009
I am trying to loop through the text file and append each one with .xml.
Ex:
100001.xml
100003.xml
100007.xml
100008.xml
100009.xml
I have tried different variations of
while read p; do
echo "$p.zip"
done < test.txt
But it prints out weird like this
.xml01
.xml03
.xml07
.xml08
.xml09
Appending a .xml at the end of each line while removing CRLF, if present.
With sed and bash:
#!/bin/bash
sed -E $'s/\r?$/.xml/' test.txt
With awk:
awk -v suffix='.xml' '{sub(/\r?$/,suffix)}1' test.txt
Using it in a bash loop:
#!/bin/bash
while IFS='' read -r filename
do
printf '%q\n' "$filename"
done < <(
awk -v suffix='.xml' '{sub(/\r?$/,suffix)}1' test.txt
)
Or doing the whole thing in pure shell:
while IFS='' read -r filename
do
fullname="${filename%\r}.xml"
printf '%s\n' "$fullname"
done < test.txt
#!/bin/bash
{ cat sample.txt; echo; } | while read -r -a A_Name; do
if [ ! -z "${A_Name[0]}" ]; then
echo " ${A_Name[0]%.isx} "
fi
done
I am trying to display contents of a text file (which includes .isx files) using while loop but when i try to eliminate extension with %, it doesnt work.
Output
.isx is appearing for first two values:
./test.sh
abc.isx
def.isx
ghi
Input
sample.txt file:
abc.isx
def.isx
ghi.isx
Please, assist. Thank you.
why so complicated?
#!/bin/bash
cat sample.txt | while read line; do
echo "${line%.isx}"
done
or with sed
sed "s/\.isx//" sample.txt >output.txt
or with sed and inplace replacement
sed -i "s/\.isx//" sample.txt
How do I add a string after each line in a file using bash? Can it be done using the sed command, if so how?
If your sed allows in place editing via the -i parameter:
sed -e 's/$/string after each line/' -i filename
If not, you have to make a temporary file:
typeset TMP_FILE=$( mktemp )
touch "${TMP_FILE}"
cp -p filename "${TMP_FILE}"
sed -e 's/$/string after each line/' "${TMP_FILE}" > filename
I prefer echo. using pure bash:
cat file | while read line; do echo ${line}$string; done
I prefer using awk.
If there is only one column, use $0, else replace it with the last column.
One way,
awk '{print $0, "string to append after each line"}' file > new_file
or this,
awk '$0=$0"string to append after each line"' file > new_file
If you have it, the lam (laminate) utility can do it, for example:
$ lam filename -s "string after each line"
Pure POSIX shell and sponge:
suffix=foobar
while read l ; do printf '%s\n' "$l" "${suffix}" ; done < file |
sponge file
xargs and printf:
suffix=foobar
xargs -L 1 printf "%s${suffix}\n" < file | sponge file
Using join:
suffix=foobar
join file file -e "${suffix}" -o 1.1,2.99999 | sponge file
Shell tools using paste, yes, head
& wc:
suffix=foobar
paste file <(yes "${suffix}" | head -$(wc -l < file) ) | sponge file
Note that paste inserts a Tab char before $suffix.
Of course sponge can be replaced with a temp file, afterwards mv'd over the original filename, as with some other answers...
This is just to add on using the echo command to add a string at the end of each line in a file:
cat input-file | while read line; do echo ${line}"string to add" >> output-file; done
Adding >> directs the changes we've made to the output file.
Sed is a little ugly, you could do it elegantly like so:
hendry#i7 tmp$ cat foo
bar
candy
car
hendry#i7 tmp$ for i in `cat foo`; do echo ${i}bar; done
barbar
candybar
carbar
I have been working in bash, and need to create a string argument. bash is a newish for me, to the point that I dont know how to build a string in bash from a list.
// foo.txt is a list of abs file names.
/foo/bar/a.txt
/foo/bar/b.txt
/delta/test/b.txt
should turn into: a.txt,b.txt,b.txt
OR: /foo/bar/a.txt,/foo/bar/b.txt,/delta/test/b.txt
code
s = ""
for file in $(cat foo.txt);
do
#what goes here? s += $file ?
done
myShellScript --script $s
I figure there was an easy way to do this.
with for loop:
for file in $(cat foo.txt);do echo -n "$file",;done|sed 's/,$/\n/g'
with tr:
cat foo.txt|tr '\n' ','|sed 's/,$/\n/g'
only sed:
sed ':a;N;$!ba;s/\n/,/g' foo.txt
This seems to work:
#!/bin/bash
input="foo.txt"
while IFS= read -r var
do
basename $var >> tmp
done < "$input"
paste -d, -s tmp > result.txt
output: a.txt,b.txt,b.txt
basename gets you the file names you need and paste will put them in the order you seem to need.
The input field separator can be used with set to create split/join functionality:
# split the lines of foo.txt into positional parameters
IFS=$'\n'
set $(< foo.txt)
# join with commas
IFS=,
echo "$*"
For just the file names, add some sed:
IFS=$'\n'; set $(sed 's|.*/||' foo.txt); IFS=,; echo "$*"
I would like to remove a file name only from the following configuration file.
Configuration File -- test.conf
knowledgebase/arun/test.rf
knowledgebase/arunraj/tester/test.drl
knowledgebase/arunraj2/arun/test/tester.drl
The above file should be read. And removed contents should went to another file called output.txt
Following are my try. It is not working to me at all. I am getting empty files only.
#!/bin/bash
file=test.conf
while IFS= read -r line
do
# grep --exclude=*.drl line
# awk 'BEGIN {getline line ; gsub("*.drl","", line) ; print line}'
# awk '{ gsub("/",".drl",$NF); print line }' arun.conf
# awk 'NF{NF--};1' line arun.conf
echo $line | rev | cut -d'/' -f 1 | rev >> output.txt
done < "$file"
Expected Output :
knowledgebase/arun
knowledgebase/arunraj/tester
knowledgebase/arunraj2/arun/test
There's the dirname command to make it easy and reliable:
#!/bin/bash
file=test.conf
while IFS= read -r line
do
dirname "$line"
done < "$file" > output.txt
There are Bash shell parameter expansions that will work OK with the list of names given but won't work reliably for some names:
file=test.conf
while IFS= read -r line
do
echo "${line%/*}"
done < "$file" > output.txt
There's sed to do the job — easily with the given set of names:
sed 's%/[^/]*$%%' test.conf > output.txt
It's harder if you have to deal with names like /plain.file (or plain.file — the same sorts of edge cases that trip up the shell expansion).
You could add Perl, Python, Awk variants to the list of ways of doing the job.
You can get the path like this:
path=${fullpath%/*}
It cuts away the string after the last /
Using awk one liner you can do this:
awk 'BEGIN{FS=OFS="/"} {NF--} 1' test.conf
Output:
knowledgebase/arun
knowledgebase/arunraj/tester
knowledgebase/arunraj2/arun/test