I have tried:
echo -e "egg\t \t\t salad" | sed -E 's/[[:blank:]]+/\t/g'
Which results in:
eggtsalad
And...
echo -e "egg\t \t\t salad" | sed -E 's/[[:blank:]]+/\\t/g'
Which results in:
egg\tsalad
What I would like:
egg salad
Try: Ctrl+V and then press Tab.
Use ANSI-C style quoting: $'string'
sed $'s/foo/\t/'
So in your example, simply add a $:
echo -e "egg\t \t\t salad" | sed -E $'s/[[:blank:]]+/\t/g'
OSX's sed only understands \t in the pattern, not in the replacement doesn't understand \t at all, since it's essentially the ancient 4.2BSD sed left over from 1982 or thenabouts. Use a literal tab (which in bash and vim is Ctrl+V, Tab), or install GNU coreutils to get a more reasonable sed.
Another option is to use $(printf '\t') to insert a tab, e.g.:
echo -e "egg\t \t\t salad" | sed -E "s/[[:blank:]]+/$(printf '\t')/g"
try awk
echo -e "egg\t \t\t salad" | awk '{gsub(/[[:blank:]]+/,"\t");print}'
A workaround for tab on osx is to use "\ ", an escape char followed by four spaces.
If you are trying to find the last instance of a pattern, say a " })};" and insert a file on a newline after that pattern, your sed command on osx would look like this:
sed -i '' -e $'/^\ \})};.*$/ r fileWithTextIWantToInsert' FileIWantToChange
The markup makes it unclear: the escape char must be followed by four spaces in order for sed to register a tab character on osx.
The same trick works if the pattern you want to find is preceded by two spaces, and I imagine it will work for finding a pattern preceded by any number of spaces as well.
Related
this is my original string:
NetworkManager/system connections/Wired 1.nmconnection:14 address1=10.1.10.71/24,10.1.10.1
I want to only add back slash to all the spaces before ':'
so, this is what I finally want:
NetworkManager/system\ connections/Wired\ 1.nmconnection:14 address1=10.1.10.71/24,10.1.10.1
I need to do this in bash, so, sed, awk, grep are all ok for me.
I have tried following sed, but none of them work
echo NetworkManager/system connections/Wired 1.nmconnection:14 address1=10.1.10.71/24,10.1.10.1 | sed 's/ .*\(:.*$\)/\\ .*\1/g'
echo NetworkManager/system connections/Wired 1.nmconnection:14 address1=10.1.10.71/24,10.1.10.1 | sed 's/\( \).*\(:.*$\)/\\ \1.*\2/g'
echo NetworkManager/system connections/Wired 1.nmconnection:14 address1=10.1.10.71/24,10.1.10.1 | sed 's/ .*\(:.*$\)/\\ \1/g'
echo NetworkManager/system connections/Wired 1.nmconnection:14 address1=10.1.10.71/24,10.1.10.1 | sed 's/\( \).*\(:.*$\)/\\ \1\2/g'
thanks for answering my question.
I am still quite newbie to stackoverflow, I don't know how to control the format in comment.
so, I just edit my original question
my real story is:
when I do grep or use cscope to search keyword, for example "address1" under /etc folder.
the result would be like:
./NetworkManager/system connections/Wired 1.nmconnection:14 address1=10.1.10.71/24,10.1.10.1
if I use vim to open file under cursor, suppose my vim cursor is now at word "NetworkManager",
then vim will understand it as
"./NetworkManager/system"
that's why I want to add "\" before space, so the search result would be more vim friendly:)
I did try to change cscope's source code, but very difficult to fully achieve this. so have to do a post replacement:(
If you only want to do the replacements if there is a : present in the string, you can check if there are at least 2 columns, setting the (output)field separator to a colon.
Data:
cat file michaelvandam#Michaels-MacBook-Pro
NetworkManager/system connections/Wired 1.nmconnection:14 address1=10.1.10.71/24,10.1.10.1
NetworkManager/system connections/Wired 1.nmconnection 14 address1=10.1.10.71/24,10.1.10.1%
Example in awk:
awk 'BEGIN {FS=OFS=":"}{if(NF>1)gsub(" ","\\ ",$1)}1' file
Output
NetworkManager/system\ connections/Wired\ 1.nmconnection:14 address1=10.1.10.71/24,10.1.10.1
NetworkManager/system connections/Wired 1.nmconnection 14 address1=10.1.10.71/24,10.1.10.1
This could be simply done in awk program, with your shown samples, please try following.
awk 'BEGIN{FS=OFS=":"} {gsub(/ /,"\\\\&",$1)} 1' Input_file
Explanation: Simple explanation would be, setting field separator and output field separator as : for this program. Then in main program using gsub(Global substitution) function of awk. Where substituting space with \ in 1st field only(as per OP's remarks it should be done before :) and printing line then.
An idea for a perl one liner in bash to use \G and \K (similar #CarySwoveland's comment).
perl -pe 's/\G[^ :]*\K /\\ /g' myfile
See this demo at tio.run or a pattern demo at regex101.
This might work for you (GNU sed):
sed -E ':a;s/^([^: ]*) /\1\n/;ta;s/\n/\\ /g' file
Replace spaces before : by newlines then replace newlines by \ 's.
Alternative using the hold space:
sed -E 's/:/\n:/;h;s/ /\\ /g;G;s/\n.*\n//' file
Split the line on the first :.
Amend the front section, remove the middle and append the unadulterated back section.
My answer is ugly and I think RavinderSingh13's answer is THE ONE, but I already took the time to write mine and it works (It's written step by step, but it's a one line command):
I got inspired by HatLess answer:
first get the text before the : with cut (I put the string in a file to make it easy to read, but this works on echo):
cut -d':' -f1 infile
Then replace spaces using sed:
cut -d':' -f1 infile | sed 's/\([a-z]\) /\1\\ /g'
Then echo the output with no new line:
echo -n "$(cut -d':' -f1 infile | sed -e 's/\([a-z]\) /\1\\ /g')"
Add the missing : and what comes after it:
echo -n "$(cut -d':' -f1 infile | sed -e 's/\([a-z]\) /\1\\ /g')" | cat - <(echo -n :) | cat - <(cut -d':' -f2 infile)
Using Sed I tried but it did not worked out.
Basically, I have a string say:-
Input:-
'http://www.google.com/photos'
Output required:-
http://www.google.com
I tried using sed but escaping ' is not possible.
what i did was:-
sed 's/\'//' | sed 's/photos//'
sed for photos worked but for ' it didn't.
Please suggest what can be the solution.
Escaping ' in sed is possible via a workaround:
sed 's/'"'"'//g'
# |^^^+--- bash string with the single quote inside
# | '--- return to sed string
# '------- leave sed string and go to bash
But for this job you should use tr:
tr -d "'"
Perl Replacements have a syntax identical to sed, works better than sed, is installed almost in every system by default and works for all machines the same way (portability):
$ echo "'http://www.google.com/photos'" |perl -pe "s#\'##g;s#(.*//.*/)(.*$)#\1#g"
http://www.google.com/
Mind that this solution will keep only the domain name with http in front, discarding all words following http://www.google.com/
If you want to do it with sed , you can use sed "s/'//g" as advised by Wiktor Stribiżew in comments.
PS: I sometimes refer to special chars with their ascii hex code of the special char as advised by man ascii, which is \x27 for '
So for sed you can do it:
$ echo "'http://www.google.com/photos'" |sed -r "s#'##g; s#(.*//.*/)(.*$)#\1#g;"
http://www.google.com/
# sed "s#\x27##g' will also remove the single quote using hex ascii code.
$ echo "'http://www.google.com/photos'" |sed -r "s#'##g; s#(.*//.*)(/.*$)#\1#g;"
http://www.google.com #Without the last slash
If your string is stored in a variable, you can achieve above operations with pure bash, without the need of external tools like sed or perl like this:
$ a="'http://www.google.com/photos'" && a="${a:1:-1}" && echo "$a"
http://www.google.com/photos
# This removes 1st and last char of the variable , whatever this char is.
$ a="'http://www.google.com/photos'" && a="${a:1:-1}" && echo "${a%/*}"
http://www.google.com
#This deletes every char from the end of the string up to the first found slash /.
#If you need the last slash you can just add it to the echo manually like echo "${a%/*}/" -->http://www.google.com/
It's unclear if the ' are actually around your string, although this should take care it:
str="'http://www.google.com/photos'"
echo "$str" | sed s/\'//g | sed 's/\/photos//g'
Combined:
echo "$str" | sed -e "s/'//g" -e 's/\/photos//g'
Using tr:
echo "$str" | sed -e "s/\/photos//g" | tr -d \'
Result:
http://www.google.com
If the single quotes are not around your string it should work regardless.
I'm trying swap words around with sed, not replace because that's what I keep finding on Google search.
I don't know if it's the regex that I'm getting wrong. I did a search for everything before a char and everything after a char, so that's how I got the regex.
echo xxx,aaa | sed -r 's/[^,]*/[^,]*$/'
or
echo xxx/aaa | sed -r 's/[^\/]*/[^\/]*$/'
I am getting this output:
[^,]*$,aaa
or this:
[^,/]*$/aaa
What am I doing wrong?
For the first sample, you should use:
echo xxx,aaa | sed 's/\([^,]*\),\([^,]*\)/\2,\1/'
For the second sample, simply use a character other than slash as the delimiter:
echo xxx/aaa | sed 's%\([^/]*\)/\([^/]*\)%\2/\1%'
You can also use \{1,\} to formally require one or more:
echo xxx,aaa | sed 's/\([^,]\{1,\}\),\([^,]\{1,\}\)/\2,\1/'
echo xxx/aaa | sed 's%\([^/]\{1,\}\)/\([^/]\{1,\}\)%\2/\1%'
This uses the most portable sed notation; it should work anywhere. With modern versions that support extended regular expressions (-r with GNU sed, -E with Mac OS X or BSD sed), you can lose some of the backslashes and use + in place of * which is more precisely what you're after (and parallels \{1,\} much more succinctly):
echo xxx,aaa | sed -E 's/([^,]+),([^,]+)/\2,\1/'
echo xxx/aaa | sed -E 's%([^/]+)/([^/]+)%\2/\1%'
With sed it would be:
sed 's#\([[:alpha:]]\+\)/\([[:alpha:]]\+\)#\2,\1#' <<< 'xxx/aaa'
which is simpler to read if you use extended posix regexes with -r:
sed -r 's#([[:alpha:]]+)/([[:alpha:]]+)#\2/\1#' <<< 'xxx/aaa'
I'm using two sub patterns ([[:alpha:]]+) which can contain one or more letters and are separated by a /. In the replacement part I reassemble them in reverse order \2/\1. Please also note that I'm using # instead of / as the delimiter for the s command since / is already the field delimiter in the input data. This saves us to escape the / in the regex.
Btw, you can also use awk for that, which is pretty easy to read:
awk -F'/' '{print $2,$1}' OFS='/' <<< 'xxx/aaa'
So I have a bash script which is working perfectly except for one issue with sed.
full=$(echo $full | sed -e 's/\b'$first'\b/ /' -e 's/ / /g')
This would work great except there are instances where the variable $first is preceeded immediately by a period, not a blank space. In those instances, I do not want the variable removed.
Example:
full="apple.orange orange.banana apple.banana banana";first="banana"
full=$(echo $full | sed -e 's/\b'$first'\b/ /' -e 's/ / /g')
echo $first $full;
I want to only remove the whole word banana, and not make any change to orange.banana or apple.banana, so how can I get sed to ignore the dot as a delimiter?
You want "banana" that is preceded by beginning-of-string or a space, and followed by a space or end-of-string
$ sed -r 's/(^|[[:blank:]])'"$first"'([[:blank:]]|$)/ /g' <<< "$full"
apple.orange orange.banana apple.banana
Note the use of -r option (for bsd sed, use -E) that enables extended regular expressions -- allow us to omit a lot of backslashes.
I have a textfile in which some words are printed in ALL CAPS. I want to be able to just convert everything in the textfile to lowercase, using sed. That means that the first sentence would then read, 'i have a textfile in which some words are printed in all caps.'
With tr:
# Converts upper to lower case
$ tr '[:upper:]' '[:lower:]' < input.txt > output.txt
# Converts lower to upper case
$ tr '[:lower:]' '[:upper:]' < input.txt > output.txt
Or, sed on GNU (but not BSD or Mac as they don't support \L or \U):
# Converts upper to lower case
$ sed -e 's/\(.*\)/\L\1/' input.txt > output.txt
# Converts lower to upper case
$ sed -e 's/\(.*\)/\U\1/' input.txt > output.txt
If you have GNU extensions, you can use sed's \L (lower entire match, or until \L [lower] or \E [end - toggle casing off] is reached), like so:
sed 's/.*/\L&/' <input >output
Note: '&' means the full match pattern.
As a side note, GNU extensions include \U (upper), \u (upper next character of match), \l (lower next character of match). For example, if you wanted to camelcase a sentence:
$ sed -E 's/\w+/\u&/g' <<< "Now is the time for all good men..." # Camel Case
Now Is The Time For All Good Men...
Note: Since the assumption is we have GNU extensions, we can use sequences such as \w (match a word character) and the -E (extended regex) option, which relieves you of having to escape the one-or-more quantifier (+) and certain other special regex characters.
You also can do this very easily with awk, if you're willing to consider a different tool:
echo "UPPER" | awk '{print tolower($0)}'
Here are many solutions :
To upercaser with perl, tr, sed and awk
perl -ne 'print uc'
perl -npe '$_=uc'
perl -npe 'tr/[a-z]/[A-Z]/'
perl -npe 'tr/a-z/A-Z/'
tr '[a-z]' '[A-Z]'
sed y/abcdefghijklmnopqrstuvwxyz/ABCDEFGHIJKLMNOPQRSTUVWXYZ/
sed 's/\([a-z]\)/\U\1/g'
sed 's/.*/\U&/'
awk '{print toupper($0)}'
To lowercase with perl, tr, sed and awk
perl -ne 'print lc'
perl -npe '$_=lc'
perl -npe 'tr/[A-Z]/[a-z]/'
perl -npe 'tr/A-Z/a-z/'
tr '[A-Z]' '[a-z]'
sed y/ABCDEFGHIJKLMNOPQRSTUVWXYZ/abcdefghijklmnopqrstuvwxyz/
sed 's/\([A-Z]\)/\L\1/g'
sed 's/.*/\L&/'
awk '{print tolower($0)}'
Complicated bash to lowercase :
while read v;do v=${v//A/a};v=${v//B/b};v=${v//C/c};v=${v//D/d};v=${v//E/e};v=${v//F/f};v=${v//G/g};v=${v//H/h};v=${v//I/i};v=${v//J/j};v=${v//K/k};v=${v//L/l};v=${v//M/m};v=${v//N/n};v=${v//O/o};v=${v//P/p};v=${v//Q/q};v=${v//R/r};v=${v//S/s};v=${v//T/t};v=${v//U/u};v=${v//V/v};v=${v//W/w};v=${v//X/x};v=${v//Y/y};v=${v//Z/z};echo "$v";done
Complicated bash to uppercase :
while read v;do v=${v//a/A};v=${v//b/B};v=${v//c/C};v=${v//d/D};v=${v//e/E};v=${v//f/F};v=${v//g/G};v=${v//h/H};v=${v//i/I};v=${v//j/J};v=${v//k/K};v=${v//l/L};v=${v//m/M};v=${v//n/N};v=${v//o/O};v=${v//p/P};v=${v//q/Q};v=${v//r/R};v=${v//s/S};v=${v//t/T};v=${v//u/U};v=${v//v/V};v=${v//w/W};v=${v//x/X};v=${v//y/Y};v=${v//z/Z};echo "$v";done
Simple bash to lowercase :
while read v;do echo "${v,,}"; done
Simple bash to uppercase :
while read v;do echo "${v^^}"; done
Note that ${v,} and ${v^} only change the first letter.
You should use it that way :
(while read v;do echo "${v,,}"; done) < input_file.txt > output_file.txt
I like some of the answers here, but there is a sed command that should do the trick on any platform:
sed 'y/ABCDEFGHIJKLMNOPQRSTUVWXYZ/abcdefghijklmnopqrstuvwxyz/'
Anyway, it's easy to understand. And knowing about the y command can come in handy sometimes.
If you have GNU sed (likely on Linux, but not on *BSD or macOS):
echo "Hello MY name is SUJIT " | sed 's/./\L&/g'
Output:
hello my name is sujit
If you are using posix sed
Selection for any case for a pattern (converting the searched pattern with this sed than use the converted pattern in you wanted command using regex:
echo "${MyOrgPattern} | sed "s/[aA]/[aA]/g;s/[bB]/[bB]/g;s/[cC]/[cC]/g;s/[dD]/[dD]/g;s/[eE]/[eE]/g;s/[fF]/[fF]/g;s/[gG]/[gG]/g;s/[hH]/[hH]/g;s/[iI]/[iI]/g;s/[jJ]/[jJ]/g;s/[kK]/[kK]/g;s/[lL]/[lL]/g;s/[mM]/[mM]/g;s/[nN]/[nN]/g;s/[oO]/[oO]/g;s/[pP]/[pP]/g;s/[qQ]/[qQ]/g;s/[rR]/[rR]/g;s/[sS]/[sS]/g;s/[tT]/[tT]/g;s/[uU]/[uU]/g;s/[vV]/[vV]/g;s/[wW]/[wW]/g;s/[xX]/[xX]/g;s/[yY]/[yY]/g;s/[zZ]/[zZ]/g" | read -c MyNewPattern
YourInputStreamCommand | egrep "${MyNewPattern}"
convert in lower case
sed "s/[aA]/a/g;s/[bB]/b/g;s/[cC]/c/g;s/[dD]/d/g;s/[eE]/e/g;s/[fF]/f/g;s/[gG]/g/g;s/[hH]/h/g;s/[iI]/i/g;s/j/[jJ]/g;s/[kK]/k/g;s/[lL]/l/g;s/[mM]/m/g;s/[nN]/n/g;s/[oO]/o/g;s/[pP]/p/g;s/[qQ]/q/g;s/[rR]/r/g;s/[sS]/s/g;s/[tT]/t/g;s/[uU]/u/g;s/[vV]/v/g;s/[wW]/w/g;s/[xX]/x/g;s/[yY]/y/g;s/[zZ]/z/g"
same for uppercase replace lower letter between // by upper equivalent in the sed
Have fun
short, sweet and you don't even need redirection :-)
perl -p -i -e 'tr/A-Z/a-z/' file
Instead of typing this long expression:
sed 'y/ABCDEFGHIJKLMNOPQRSTUVWXYZ/abcdefghijklmnopqrstuvwxyz/' input
One could use this:
sed 'y/'$(printf "%s" {A..Z} "/" {a..z} )'/' input