getting first part of a string that has two parts - bash

I have a string that has two parts (path and owner) both separated by a space.
This is the input file input.txt
/dir1/dir2/file1 #owner1
/dir1/dir2/foo\ bar #owner2
I want to extract all the paths to a separate output file - output.txt
I cannot use space as delimiter since paths can also have filenames with space and delimiter in them
/dir1/dir2/file1
/dir1/dir2/foo\ bar

Here could be a different way of doing it with rev + GNU grep:
rev file | grep -oP '.*# \K.*' | rev
OR
rev file | grep -oP '.*#\s+\K.*' | rev
With original simple solution go with:
awk -F' #' '{print $1}' Input_file

Assuming spaces that shouldn't be parsed as delimiters are escaped by a backslash as in your sample, you could use the following regex :
^(\\ |[^ ])*
For instance with grep :
grep -oE '^(\\ |[^ ])*'
The regex matches from the start of the line any number of either a backslash followed by a space or any other character than a space and will stop at the first occurence of a space that isn't preceded by a backslash.
You can try it here.

I would trim the ending part with sed.
sed 's/ [^ ]*$//' /path/to/file
This will match from the end of the line:
(blank) matches the space character
[^ ]* matches the longest string that contains no spaces, i.e. #owner1
$ matches the end of the line
And they will be replaced by nothing, which will act as if you deleted the matched string.

A one-line would do it:
while read p _; do printf '%q\n' "$p"; done <input.txt >output.txt

You can put them in an array and process
mapfile test < input.txt; test=("${test[#]% *}")
echo "${test[#]}"
echo "${test[0]}"
echo "${test[1]}"

You can try with simple awk
awk ' { $NF=""; print } '
Try it here https://ideone.com/W8J1ZO

Related

Extract string between qoutes in a script

my text-
(
"en-US"
)
what i need -
en-US
currently im able to get it by piping it with
... | tr -d '[:space:]' | sed s/'("'// | sed s/'("'// | sed s/'")'//
I wonder if there is a simple way to extract the string between the qoutes rather than chopping off useless parts one by one
... | grep -oP '(?<=").*(?=")'
Explanation:
-o: Only output matching string
-P: Use Perl style RegEx
(?<="): Lookbehind, so only match text that is preceded by a double quote
.*: Match any characters
(?="): Lookahead, so only match text that is followed by a double quote
With sed
echo '(
"en-US"
)' | sed -rn 's/.*"(.*)".*/\1/p'
with 2 commands
echo '(
"en-US"
)' | tr -d "\n" | cut -d '"' -f2
Could you please try following. Where var is the bash variable haveing shown sample value stored in it.
echo "$var" | awk 'match($0,/".*"/){print substr($0,RSTART+1,RLENGTH-2)}'
Explanation: Following is only for explanation purposes.
echo "$var" | ##Using echo to print variable named var and using |(pipe) to send its output to awk command as an Input.
awk ' ##Starting awk program from here.
match($0,/".*"/){ ##using match function of awk to match a regex which is to match from till next occurrence of " by this match 2 default variables named RSTART and RLENGTH will be set as per values.
print substr($0,RSTART+1,RLENGTH-2) ##Where RSTART means starting point index of matched regex and RLENGTH means matched regex length, here printing sub-string whose starting point is RSTART and ending point of RLENGTH to get only values between " as per request.
}' ##Closing awk command here.
Consider using
... | grep -o '"[^"]\{1,\}"' | sed -e 's/^"//' -e 's/"$//'
grep will extract all substrings between quotes (excluding empty ones), the sed later will remove the quotes on both ends.
And this one ?
... | grep '"' | cut -d '"' -f 2
It works if you have just 1 quoted value by line.

awk to ignore leading and trailing space and blank lines and commented lines if any from a file

Need help on awk
awk to ignore leading and trailing space and blank lines and commented lines if any from a file
Here you go,
grep "MyText" FromMyLog.log |awk -F " " '{print $2}'|awk -F "#" '{print $1}'
Here MyText is the key to grep from file FromMyLog.log
-F is used to avoid the following value, here space between quotes.
'{print $2}' will print the 2nd argument from the output, you can use $1, $2 as your requirement.
awk -F "#" This will ignore the commented lines.
This is just a hint for you, Modify the code with your requirements. This works for me while grep.
grep -v '^$\|^\s*\#' <filename> or egrep -v '^[[:space:]]*$|^ *#' <file_name> (if white spaces)
I think this is what you were asking for:
$> echo -e ' abc \t
\t efg
# alskdjfl
#
awk
# askdfh
' |
awk '
# match if first none space character is not a hash sign
/^[[:space:]]*[^#]/ {
# delete any spaces from start and end of line
sub(/^[[:space:]]*/, "");
sub(/[[:space:]]*$/, "", NF); # `NF` is Number of Fields
print
}'
abc
efg
awk
This can be folded onto a single line if so needed. Any problems, an actual example of the input (in a code block in your question) would be helpful.
Here's one way to extract required content ignoring spaces
FILE CONTENT
Server: 192.168.XX.XX
Address 1: 192.168.YY.YY
Name: central.google.com
Now to extract the server's address without spaces.
COMMAND
awk -F':' '/Server/ '{print $2}' YOURFILENAME | tr -s " "
option -s for squeezing the repetition of spaces.
which gives,
192.168.XX.XX
Here, notice that there is one leading space in the address.
To completely ignore spaces you can change that to,
awk -F':' '/Server/ '{print $2}' YOURFILENAME | tr -d [:space:]
option -d for removing particular characters, which is [:space:] here.
which gives,
192.168.YY.YY
without any leading or trailing spaces.
tr is an UNIX utility for translating, or deleting, or squeezing repeated characters. tr refers to translate here.
Examples:
tr [:lower:] [:upper:]
gives,
YOUAREAWESOME
for
youareawesome
Hope that helps.

Replacing/removing excess white space between columns in a file

I am trying to parse a file with similar contents:
I am a string 12831928
I am another string 41327318
A set of strings 39842938
Another string 3242342
I want the out file to be tab delimited:
I am a string\t12831928
I am another string\t41327318
A set of strings\t39842938
Another string\t3242342
I have tried the following:
sed 's/\s+/\t/g' filename > outfile
I have also tried cut, and awk.
Just use awk:
$ awk -F' +' -v OFS='\t' '{sub(/ +$/,""); $1=$1}1' file
I am a string 12831928
I am another string 41327318
A set of strings 39842938
Another string 3242342
Breakdown:
-F' +' # tell awk that input fields (FS) are separated by 2 or more blanks
-v OFS='\t' # tell awk that output fields are separated by tabs
'{sub(/ +$/,""); # remove all trailing blank spaces from the current record (line)
$1=$1} # recompile the current record (line) replacing FSs by OFSs
1' # idiomatic: any true condition invokes the default action of "print"
I highly recommend the book Effective Awk Programming, 4th Edition, by Arnold Robbins.
The difficulty comes in the varying number of words per-line. While you can handle this with awk, a simple script reading each word in a line into an array and then tab-delimiting the last word in each line will work as well:
#!/bin/bash
fn="${1:-/dev/stdin}"
while read -r line || test -n "$line"; do
arr=( $(echo "$line") )
nword=${#arr[#]}
for ((i = 0; i < nword - 1; i++)); do
test "$i" -eq '0' && word="${arr[i]}" || word=" ${arr[i]}"
printf "%s" "$word"
done
printf "\t%s\n" "${arr[i]}"
done < "$fn"
Example Use/Output
(using your input file)
$ bash rfmttab.sh < dat/tabfile.txt
I am a string 12831928
I am another string 41327318
A set of strings 39842938
Another string 3242342
Each number is tab-delimited from the rest of the string. Look it over and let me know if you have any questions.
sed -E 's/[ ][ ]+/\\t/g' filename > outfile
NOTE: the [ ] is openBracket Space closeBracket
-E for extended regular expression support.
The double brackets [ ][ ]+ is to only substitute tabs for more than 1 consecutive space.
Tested on MacOS and Ubuntu versions of sed.
Your input has spaces at the end of each line, which makes things a little more difficult than without. This sed command would replace the spaces before that last column with a tab:
$ sed 's/[[:blank:]]*\([^[:blank:]]*[[:blank:]]*\)$/\t\1/' infile | cat -A
I am a string^I12831928 $
I am another string^I41327318 $
A set of strings^I39842938 $
Another string^I3242342 $
This matches – anchored at the end of the line – blanks, non-blanks and again blanks, zero or more of each. The last column and the optional blanks after it are captured.
The blanks before the last column are then replaced by a single tab, and the rest stays the same – see output piped to cat -A to show explicit line endings and ^I for tab characters.
If there are no blanks at the end of each line, this simplifies to
sed 's/[[:blank:]]*\([^[:blank:]]*\)$/\t\1/' infile
Notice that some seds, notably BSD sed as found in MacOS, can't use \t for tab in a substitution. In that case, you have to use either '$'\t'' or '"$(printf '\t')"' instead.
another approach, with gnu sed and rev
$ rev file | sed -r 's/ +/\t/1' | rev
You have trailing spaces on each line. So you can do two sed expressions in one go like so:
$ sed -E -e 's/ +$//' -e $'s/ +/\t/' /tmp/file
I am a string 12831928
I am another string 41327318
A set of strings 39842938
Another string 3242342
Note the $'s/ +/\t/': This tells bash to replace \t with an actual tab character prior to invoking sed.
To show that these deletions and \t insertions are in the right place you can do:
$ sed -E -e 's/ +$/X/' -e $'s/ +/Y/' /tmp/file
I am a stringY12831928X
I am another stringY41327318X
A set of stringsY39842938X
Another stringY3242342X
Simple and without invisible semantic characters in the code:
perl -lpe 's/\s+$//; s/\s\s+/\t/' filename
Explanation:
Options:
-l: remove LF during processing (in this case)
-p: loop over records (like awk) and print
-e: code follows
Code:
remove trailing whitespace
change two or more whitespace to tab
Tested on OP data. The trailing spaces are removed for consistency.

Replace pipe character "|" with escaped pip character "\|" in string in bash script

I am trying to replace a pipe character in an String with the escaped character in it:
Input: "text|jdbc"
Output: "text\|jdbc"
I tried different things with tr:
echo "text|jdbc" | tr "|" "\\|"
...
But none of them worked.
Any help would be appreciated.
Thank you,
tr is good for one-to-one mapping of characters (read "translate").
\| is two characters, you cannot use tr for this. You can use sed:
echo 'text|jdbc' | sed -e 's/|/\\|/'
This example replaces one |. If you want to replace multiple, add the g flag:
echo 'text|jdbc' | sed -e 's/|/\\|/g'
An interesting tip by #JuanTomas is to use a different separator character for better readability, for example:
echo 'text|jdbc' | sed -e 's_|_\\|_g'
You can take advantage of the fact that | is a special character in bash, which means the %q modifier used by printf will escape it for you:
$ printf '%q\n' "text|jdbc"
text\|jdbc
A more general solution that doesn't require | to be treated specially is
$ f="text|jdbc"
$ echo "${f//|/\\|}"
text\|jdbc
${f//foo/bar} expands f and replaces every occurance of foo with bar. The operator here is /; when followed by another /, it replaces all occurrences of the search pattern instead of just the first one. For example:
$ f="text|jdbc|two"
$ echo "${f/|/\\|}"
text\|jdbc|two
$ echo "${f//|/\\|}"
text\|jdbc\|two
You can try with awk:
echo "text|jdbc" | awk -F'|' '$1=$1' OFS="\\\|"

How to retrieve digits including the separator "."

I am using grep to get a string like this: ANS_LENGTH=266.50 then I use sed to only get the digits: 266.50
This is my full command: grep --text 'ANS_LENGTH=' log.txt | sed -e 's/[^[[:digit:]]]*//g'
The result is : 26650
How can this line be changed so the result still shows the separator: 266.50
You don't need grep if you are going to use sed. Just use sed' // to match the lines you need to print.
sed -n '/ANS_LENGTH/s/[^=]*=\(.*\)/\1/p' log.txt
-n will suppress printing of lines that do not match /ANS_LENGTH/
Using captured group we print the value next to = sign.
p flag at the end allows to print the lines that matches our //.
If your grep happens to support -P option then you can do:
grep -oP '(?<=ANS_LENGTH=).*' log.txt
(?<=...) is a look-behind construct that allows us to match the lines you need. This requires the -P option
-o allows us to print only the value part.
You need to match a literal dot as well as the digits.
Try sed -e 's/[^[[:digit:]\.]]*//g'
The dot will match any single character. Escaping it with the backslash will match only a literal dot.
Here is some awk example:
cat file:
some data ANS_LENGTH=266.50 other=22
not mye data=43
gnu awk (due to RS)
awk '/ANS_LENGTH/ {f=NR} f&&NR-1==f' RS="[ =]" file
266.50
awk '/ANS_LENGTH/ {getline;print}' RS="[ =]" file
266.50
Plain awk
awk -F"[ =]" '{for(i=1;i<=NF;i++) if ($i=="ANS_LENGTH") print $(i+1)}' file
266.50
awk '{for(i=1;i<=NF;i++) if ($i~"ANS_LENGTH") {split($i,a,"=");print a[2]}}' file
266.50

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