so the file contains data like
# entertainment
youtube.com
twitch.tv
# research
google.com
wikipedia.com
...
and I would like to pass that file as an argument in a script that would open all lines if they doesn't start with an #. Any clues on how to ?
so far what i have:
for Line in $Lines
do
case "# " in $Line start firefox $Line;; esac
done
some code that could be useful (?):
while read line; do chmod 755 "$line"; done < file.txt
grep -e '^[^#]' inputfile.txt | xargs -d '\n' firefox --new-tab
grep -e '^[^#]': Will print all lines that don't start with a sharp (comments)
xargs -d '\n' firefox --new-tab: Will pass each line that is not blank, as argument to Firefox.
Removes both the lines that start with # and empty lines.
#!/bin/bash
#
while read -r line
do
if [[ $(echo "$line" | grep -Ev "^#|^$") ]]
then
firefox --new-tab "$url" &
fi
done <file.txt
Skip the empty lines and the lines that starts with a #
#!/usr/bin/env bash
while IFS= read -r url; do
[[ "$url" == \#* || -z "$url" ]] && continue
firefox --new-tab "$url" &
done < file.txt
awk 'NF && $1!="#"{print "firefox --new-tab", $0, "&"}' file.txt | bash
I have a file that contains 10 lines with this sort of content:
aaaa,bbb,132,a.g.n.
I wanna walk throw every line, char by char and put the data before the " , " is met in an output file.
if [ $# -eq 2 ] && [ -f $1 ]
then
echo "Read nr of fields to be saved or nr of commas."
read n
nrLines=$(wc -l < $1)
while $nrLines!="1" read -r line || [[ -n "$line" ]]; do
do
for (( i=1; i<=$n; ++i ))
do
while [ read -r -n1 temp ]
do
if [ temp != "," ]
then
echo $temp > $(result$i)
else
fi
done
paste -d"\n" $2 $(result$i)
done
nrLines=$($nrLines-1)
done
else
echo "File not found!"
fi
}
In parameter $2 I have an empty file in which I will store the data from file $1 after I extract it without the " , " and add a couple of comments.
Example:
My input_file contains:
a.b.c.d,aabb,comp,dddd
My output_file is empty.
I call my script: ./script.sh input_file output_file
After execution the output_file contains:
First line info: a.b.c.d
Second line info: aabb
Third line info: comp
(yes, without the 4th line info)
You can do what you want very simply with parameter-expansion and substring-removal using bash alone. For example, take an example file:
$ cat dat/10lines.txt
aaaa,bbb,132,a.g.n.
aaaa,bbb,133,a.g.n.
aaaa,bbb,134,a.g.n.
aaaa,bbb,135,a.g.n.
aaaa,bbb,136,a.g.n.
aaaa,bbb,137,a.g.n.
aaaa,bbb,138,a.g.n.
aaaa,bbb,139,a.g.n.
aaaa,bbb,140,a.g.n.
aaaa,bbb,141,a.g.n.
A simple one-liner using native bash string handling could simply be the following and give the following results:
$ while read -r line; do echo ${line%,*}; done <dat/10lines.txt
aaaa,bbb,132
aaaa,bbb,133
aaaa,bbb,134
aaaa,bbb,135
aaaa,bbb,136
aaaa,bbb,137
aaaa,bbb,138
aaaa,bbb,139
aaaa,bbb,140
aaaa,bbb,141
Paremeter expansion w/substring removal works as follows:
var=aaaa,bbb,132,a.g.n.
Beginning at the left and removing up to, and including, the first ',' is:
${var#*,} # bbb,132,a.g.n.
Beginning at the left and removing up to, and including, the last ',' is:
${var##*,} # a.g.n.
Beginning at the right and removing up to, and including, the first ',' is:
${var%,*} # aaaa,bbb,132
Beginning at the left and removing up to, and including, the last ',' is:
${var%%,*} # aaaa
Note: the text to remove above is represented with a wildcard '*', but wildcard use is not required. It can be any allowable text. For example, to only remove ,a.g.n where the preceding number is 136, you can do the following:
${var%,136*},136 # aaaa,bbb,136 (all others unchanged)
To print 2016 th line from a file named file.txt u have to run a command like this-
sed -n '2016p' < file.txt
More-
sed -n '2p' < file.txt
will print 2nd line
sed -n '2011p' < file.txt
2011th line
sed -n '10,33p' < file.txt
line 10 up to line 33
sed -n '1p;3p' < file.txt
1st and 3th line
and so on...
For more detail, please have a look in this tutorial and this answer.
In native bash the following should do what you want, assuming you replace the contents of your script.sh with the below:
#!/bin/bash
IN_FILE=${1}
OUT_FILE=${2}
IFS=\,
while read line; do
set -- ${line}
for ((i=1; i<=${#}; i++)); do
((${i}==4)) && continue
((n+=1))
printf '%s\n' "Line ${n} info: ${!i}"
done
done < ${IN_FILE} > ${OUT_FILE}
This will not print the 4th field of each line within the input file, on a new line in the output file (I assume this is your requirement as per your comment?).
[wspace#wspace sandbox]$ awk -F"," 'BEGIN{OFS="\n"}{for(i=1; i<=NF-1; i++){print "line Info: "$i}}' data.txt
line Info: a.b.c.d
line Info: aabb
line Info: comp
This little snippet can ignore the last field.
updated:
#!/usr/bin/env bash
if [ ! -f "$1" -o $# -ne 2 ];then
echo "Usage: $(basename $0) input_file out_file"
exit 127
fi
input_file=$1
output_file=$2
: > $output_file
if [ "$(wc -l < $1)" -ne 0 ];then
while true
do
read -r -n1 char
if [ "$char" == "" ];then
break
elif [ $char != "," ];then
temp=$temp$char
else
echo "line info: $temp" >> $output_file
temp=""
fi
done < $input_file
else
echo "file $1 is empty"
fi
Maybe this is what you want
Did you try
sed "s|,|\n|g" $1 | head -n -1 > $2
I assume that only the last word would not have a comma on its right.
Try this (tested with you sample line) :
#!/bin/bash
# script.sh
echo "Number of fields to save ?"
read nf
while IFS=$',' read -r -a arr; do
newarr=${arr[#]:0:${nf}}
done < "$1"
for i in ${newarr[#]};do
printf "%s\n" $i
done > "$2"
Execute script with :
$ ./script.sh inputfile outputfile
Number of fields ?
3
$ cat outputfile
a.b.c.d
aabb
comp
All words separated with commas are stored into an array $arr
A tmp array $newarr removes last $n element ($n get the read command).
It loops over new array and prints result in $2, the outputfile.
Using bash shell:
I am trying to read a file line by line.
and every line contains two meaning full file names delimited by "``"
file:1 image_config.txt
bbbbb.mp4``thumb/hashdata.gif
bbbbb.mp4``thumb/hashdata2.gif
Shell Script
#!/bin/bash
filename="image_config.txt"
while IFS='' read -r line || [[ -n "$line" ]]; do
IFS='``' read -r -a array <<< "$line"
if [ "$line" = "" ]; then
echo lineempty
else
file=${array[0]}
hash=${array[2]}
echo $file$hash;
output=$(ffmpeg -v warning -ss 2 -t 0.8 -i $file -vf scale=200:-1 -gifflags +transdiff -y $hash);
echo $output;
# echo ${array[0]}${array[1]}${array[2]}
fi;
done < "$filename"
first time executed successfully but when loop executes second time.
variable file lost bbbbb from bbbbb.mp4
and following output comes out
Output :
user#domain [~/public_html/Videos]$ sh imager.sh
bbbbb.mp4thumb/hashdata.gif
.mp4thumb/hashdata2.gif
.mp4: No such file or directory
lineempty
Please check out Bash FAQ 89 - I'm using a loop which runs once per line of input but it only seems to run once; everything after the first line is ignored? which seems to be helpful in your case.
Aside:
There is no point in using the same character twice in IFS.
IFS=\`
Is enough.
Check out this:
var='abc``def'
IFS=\`\` read -ra arr <<< "$var"
printf '<%s>\n' "${arr[#]}"
Output:
<abc>
<>
<def>
As you can see, arr[0] is abc, arr[1] is empty and arr[2] is def, and not arr[0] is abc and arr[1] is def as one might expect.
Taken from the IFS wiki of Greycat and Lhunath Bash Guide :
The IFS variable is used in shells (Bourne, POSIX, ksh, bash) as the input field separator (or internal field separator). Essentially, it is a string of special characters which are to be treated as delimiters between words/fields when splitting a line of input.
Here is how you could do differently, avoiding a read in the read:
#!/bin/bash
filename="image_config.txt"
while IFS='' read -r line || [[ -n "$line" ]]; do
if [ "$line" = "" ]; then
echo lineempty
else
file=$( echo ${line} | awk -F \` ' { print $1 } ' )
hash=$( echo ${line} | awk -F \` ' { print $3 } ' )
echo $file$hash;
output=$(ffmpeg -v warning -ss 2 -t 0.8 -i $file -vf scale=200:-1 -gifflags +transdiff -y $hash);
echo $output;
fi;
done < "$filename"
I'm trying to put together a bash script that will search a bunch of files and if it finds a particular string in a file, it will add a new line on the line after that string and then move on to the next file.
#! /bin/bash
echo "Creating variables"
SEARCHDIR=testfile
LINENUM=1
find $SEARCHDIR* -type f -name *.xml | while read i; do
echo "Checking $i"
ISBE=`cat $i | grep STRING_TO_SEARCH_FOR`
if [[ $ISBE =~ "STRING_TO_SEARCH_FOR" ]] ; then
echo "found $i"
cat $i | while read LINE; do
((LINENUM=LINENUM+1))
if [[ $LINE == "<STRING_TO_SEARCH_FOR>" ]] ; then
echo "editing $i"
awk -v "n=$LINENUM" -v "s=new line to insert" '(NR==n) { print s } 1' $i
fi
done
fi
LINENUM=1
done
the bit I'm having trouble with is
awk -v "n=$LINENUM" -v "s=new line to insert" '(NR==n) { print s } 1' $i
if I just use $i at the end, it will output the content to the screen, if I use $i > $i then it will just erase the file and if I use $i >> $i it will get stuck in a loop until the disk fills up.
any suggestions?
Unfortunately awk dosen't have an in-place replacement option, similar to sed's -i, so you can create a temp file and then remove it:
awk '{commands}' file > tmpfile && mv tmpfile file
or if you have GNU awk 4.1.0 or newer, the -i inplace is added, so you can do:
awk -i inplace '{commands}' file
to modify the original
#cat $i | while read LINE; do
# ((LINENUM=LINENUM+1))
# if [[ $LINE == "<STRING_TO_SEARCH_FOR>" ]] ; then
# echo "editing $i"
# awk -v "n=$LINENUM" -v "s=new line to insert" '(NR==n) { print s } 1' $i
# fi
# done
# replaced by
sed -i 's/STRING_TO_SEARCH_FOR/&\n/g' ${i}
or use awk in place of sed
also
# ISBE=`cat $i | grep STRING_TO_SEARCH_FOR`
# if [[ $ISBE =~ "STRING_TO_SEARCH_FOR" ]] ; then
#by
if [ $( grep -c 'STRING_TO_SEARCH_FOR' ${i} ) -gt 0 ]; then
# if file are huge, if not directly used sed on it, it will be faster (but no echo about finding the file)
If you can, maybe use a temporary file?
~$ awk ... $i > tmpfile
~$ mv tmpfile $i
Or simply awk ... $i > tmpfile && mv tmpfile $i
Note that, you can use mktemp to create this temporary file.
Otherwise, with sed you can insert a line right after a match:
~$ cat f
auie
nrst
abcd
efgh
1234
~$ sed '/abcd/{a\
new_line
}' f
auie
nrst
abcd
new_line
efgh
1234
The command search if the line matches /abcd/, if so, it will append (a\) the line new_line.
And since sed as the -i to replace inline, you can do:
if [[ $ISBE =~ "STRING_TO_SEARCH_FOR" ]] ; then
echo "found $i"
echo "editing $i"
sed -i "/STRING_TO_SEARCH_FOR/{a
\new line to insert
}" $i
fi
This is my code
title=""
line=""
fname=$1
numoflines=$(wc -l < $fname)
for ((i=2 ; i<=$numoflines ; i++))
do
...
done
In the for loop i want to print the first word of every line into $title
and the rest of the line without the first word into $line
(using bash)
tnx
I am assuming that by print to a variable you mean add the contents of each line to the variable. To do this, you can use the bash built-in function read:
while read -r t l; do title+="$t"; line+="$l"; done < "$fname"
This will add the first word of every line to $title and the rest of the line to $line.
You can do some like this:
echo "$fname"
This is my line.
My cat is green.
title=$(awk '{print $1}' <<< "$fname")
line=$(awk '{$1="";sub(/^ /,"")}1' <<< "$fname")
echo "$title"
This
My
echo "$line"
is my line.
cat is green.
Alternative approach using the cut command:
file="./myfile.txt"
title=$(cut -f1 -d ' ' "$file")
line=$(cut -f2- -d ' ' "$file")
#check print
pr -tm <(echo -e "TITLES\n$title") <(echo -e "LINES\n$line")
for the next myfile.txt
My cat is green.
Green cats are strange.
prints
TITLES LINES
My cat is green.
Green cats are strange.
do
Tempo="$( sed -n "${i} {s/^[[:blank:]]*\([^[:blank:]]*\)[[:blank:]]*\(.*\)/title='\1';line='\2'/p;q;}" ${fname} )"
eval "${Tempo}"
done
# or
do
sed -n "${i} {p;q;}" | read Line Title
# but this does not keep content available on each OS/shell
done