Problem statement:
change every user agent that does not match A2PC or GENCOM with the user agent PROHIBITED and keep GENCOM and A2PC unchanged
Expression:
echo \"GENCOM\" | sed -r -e 's/(^((?!A2PC)(?!GENCOM).)*$)/PROHIBITED/g'
error:
sed: -e expression #1, char 41: Invalid preceding regular expression
I removed -r then error not thrown but its not working
echo \"GENDFGGH\" | sed -e 's/(^((?!A2PC)(?!GENCOM).)*$)/PROHIBITED/g'
"GENDFGGH"
Please help me for this solution
First look for your pattern and then do the sub:
# echo \"GENCsOM\" | sed -e '/^"\(GENCOM\|A2PC\)"$/! s/^.*$/PROHIBITED/'
PROHIBITED
# echo \"GENCOM\" | sed -e '/^"\(GENCOM\|A2PC\)"$/! s/^.*$/PROHIBITED/'
"GENCOM"
sed '/A2PC/ !{
/GENCOM/ ! {
s/$/PROHIBITED/
}
}' YourFile
double exclusion than a change, posix compliant
Related
I have lines that start like this: 2141058222 11/22/2017 and I want to append a ; at the end of the ten digit number like this: 2141058222; 11/22/2017.
I've tried sed with sed -i 's/^[0-9]\{10\}\\$/;&/g' which does nothing.
What am I missing?
Try this:
echo "2141058222 11/22/2017" | sed -r 's/^([0-9]{10})/&;/'
echo "2141058222 11/22/2017" | sed 's/ /; /'
Output:
2141058222; 11/22/2017
If the input is always in the format specified, GNU cut works, and might even be more efficient than sed:
cut -c -10,11- --output-delimiter ';' <<< "2141058222 11/22/2017"
Output:
2141058222; 11/22/2017
For an input file that'd be:
cut -c -10,11- --output-delimiter ';' file
How to print only string figure with the following line :
\begin{figure}[h!]
I tried :
firstLine='\begin{figure}[h!]'
echo $firstLine | sed -n 's/\\begin{\(.*\)}/\1/p'
but returns :
figure[h!] instead of figure
It seems that issue comes from [] or ! character.
firstLine='\begin{figure}[h!]'
echo "$firstLine" | sed 's/.*{\(.*\)}.*/\1/'
Output:
figure
With your code (add .*):
echo $firstLine | sed -n 's/\\begin{\(.*\)}.*/\1/p'
This might work for you (GNU sed):
sed 's/.*{\(.*\)}.*/\1/' file
This assumes there is only one {...} expression and one line.
A more rigorous solution would be:
sed -n 's/.*\\begin{\([^}]*\)}.*/\1/p' file
However nothing would be output if no match was found.
I'm trying to extract data/urls (in this case - someurl) from a file that contains them within some tag ie.
xyz>someurl>xyz
I don't mind using either awk or sed.
I think the best, easiest, way is with cut:
$ echo "xyz>someurl>xyz" | cut -d'>' -f2
someurl
With awk can be done like:
$ echo "xyz>someurl>xyz" | awk 'BEGIN { FS = ">" } ; { print $2 }'
someurl
And with sed is a little bit more tricky:
$ echo "xyz>someurl>xyz" | sed 's/\(.*\)>\(.*\)>\(.*\)/\2/g'
someurl
we get blocks of something1<something2<something3 and print the 2nd one.
grep was born to extract things:
kent$ echo "xyz>someurl>xyz"|grep -Po '>\K[^>]*(?=>)'
someurl
you could kill a fly with a bomb of course:
kent$ echo "xyz>someurl>xyz"|awk -F\> '$0=$2'
someurl
If your grep supports P option then you can use lookahead and lookbehind regular expression to identify the url.
$ echo "xyz>someurl>xyz" | grep -oP '(?<=xyz>).*(?=>xyz)'
someurl
This is just a sample to get you started not the final answer.
Is it possible to encapsulate the following pseudocode using sed?
for line in lines:
if line == "foo":
print "FOO"
else:
print "- " + line
Here's the first thing I tried:
> echo 'foo
> bar
> baz' | sed -e 's/^foo$/FOO/' -e 's/^/- /'
- FOO
- bar
- baz
This is incorrect since both substitutions are applied to the first line.
Is it possible to tell sed to perform a maximum of one substitution per line?
You can limit what lines a substitution affects, by prefixing it with a pattern:
sed -e '/^foo$/! s/^/- /' -e '/^foo$/ s//FOO/' infile
A better alternative is to use the t branch command which will go to the next line if the previous substitution succeeded:
sed 's/^foo$/FOO/; t; s/^/- /' infile
Or the more portable:
sed -e 's/^foo$/FOO/' -e t -e 's/^/- /' infile
Output in both cases:
FOO
- bar
- baz
The sed below will output the input exactly. What I'd like to do is replace all occurrences of _ with - in the first matching group (\1), but not in the second. Is this possible?
echo 'abc_foo_bar=one_two_three' | sed 's/\([^=]*\)\(=.*\)/\1\2/'
abc_foo_bar=one_two_three
So, the output I'm hoping for is:
abc-foo-bar=one_two_three
I'd prefer not to resort to awk since I'm doing a string of other sed commands too, but I'll resort to that if I have to.
Edit: Minor fix to RE
You can do this in sed using the hold space:
$ echo 'abc_foo_bar=one_two_three' | sed 'h; s/[^=]*//; x; s/=.*//; s/_/-/g; G; s/\n//g'
abc-foo-bar=one_two_three
You could use awk instead of sed as follows:
echo 'abc_foo_bar=one_two_three' | awk -F= -vOFS== '{gsub("_", "-", $1); print $1, $2}'
The output would be, as expected:
abc-foo-bar=one_two_three
You could use ghc instead of sed as follows:
echo "abc_foo_bar=one_two_three" | ghc -e "getLine >>= putStrLn . uncurry (++) . (map (\x -> if x == '_' then '-' else x) *** id) . break (== '=')"
The output would be, as expected:
abc-foo-bar=one_two_three
This might work for you:
echo 'abc_foo_bar=one_two_three' |
sed 's/^/\n/;:a;s/\n\([^_=]*\)_/\1-\n/;ta;s/\n//'
abc-foo-bar=one_two_three
Or this:
echo 'abc_foo_bar=one_two_three' |
sed 'h;s/=.*//;y/_/-/;G;s/\n.*=/=/'
abc-foo-bar=one_two_three