I use the following sed syntax in order to replace the timezone string with #timezone
actually sed command replace it ,
but in case after timezone string we have one space or more then sed not replaced it
my question what I need to change in the sed syntax in order to replace the timezone string
on the both cases
After timezone string we not have any space
After timezone string we a have space or more
sed -i '/timezone$/s/timezone/#timezone/' file
You can try:
sed -i.bak -r 's/timezone ?$/#timezone/' file
you need to add the ? after a space, that will make the space optional. Also you'll have to add the -r option to make sed understand extended regex.
Also you are not specifying the backup extension after the -i option.
Stating your two cases as one, you want to replace 'timezone' followed by zero or more spaces, when it is at the end of the line. That should be this:
sed -i 's/timezone *$/#timezone/' file
This should be an ideal solution for both your cases.
sed 's/timezone *$\|timezone/#&/' INPUT_FILE
Related
I have a line like this:
"abc/x-y-z": "^1.4"
I need to replace ^1.4with * in the same file such that the output is "abc/x-y-z": "*"
The num inside the double quotes could be any variable number.
I tried this but it is highly specific to ^1.4 number:
sed -i '21s/^1.4/*/' abc.json
With your shown samples, please try following. You need to escape ^ here to make it literal character and you need to escape . dot as well to make it treat as literal character.
sed 's/\^1\.4/*/' Input_file
OR as per OP's comment to make it dynamic try:
sed 's/\^[0-9]+\.[0-9]+/*/' Input_file
Also if you are performing it on 21st line of your file then use 21s like you tried in your attempt. This code will substitute only very 1st occurrence of ^1.4 here in case you want to substitute all occurrences then use g(globally substitution) option for above code.
I have not used -i option(to do inplace update into Input_file itself) once you are happy with results then use sed -i option in above code.
When making changes to files, I prefer the file editor ed to the stream editor sed (ed is standard, sed -i isn't, and different versions have different quirks that bite people here on a regular basis).
ed -s input.txt <<EOF
21s/"^[[:digit:]]\{1,\}\(\.[[:digit:]]\{1,\}\)\{0,1\}"/"*"/
w
EOF
On line 21, matches a quote followed by a carat followed by 1 or more digits, optionally followed by a period and another sequence of 1 or more digits and finally the trailing quote character. All that is replaced by "*", and finally the changed file is written back to disk.
Posix BREs are a pain, no? GNU ed 1.17 and newer, and NetBSD ed can take EREs instead:
ed -Es input.txt <<EOF
21s/"\^[[:digit:]]+(\.[[:digit:]]+)?"/"*"/
w
EOF
which is a lot easier to read.
I want to substring the File name in unix using sed command.
File name : Test_Test1_Test2_10082019_030013.csv.20191008-075740
I want the characters after the 3rd underscore or (all the characters after Test2 ) i need to be printed .
Can this be done using sed command?
I have tried this command
sed 's/^.*_\([^_]*\)$/\1/' <<< 'Test_Test1_Test2_10082019_030013.csv.20191008-075740'
but this is giving result as 030013.csv.20191008-075740
I need it from 10082019_030013.csv.20191008-075740
Thanks
Neha
To remove from the beginning up to including the 3rd underscore you can use
sed 's/^\([^_]*_\)\{3\}//' <<< 'Test_Test1_Test2_10082019_030013.csv.20191008-075740'
This removes the initial part that consists of 3 groups of (any number of non-underscore characters followed by an underscore). The result is
10082019_030013.csv.20191008-075740
If you use GNU sed you can switch it to extended regular expressions and omit the backslashes.
sed -r 's/^([^_]*_){3}//' <<< 'Test_Test1_Test2_10082019_030013.csv.20191008-075740'
Could you please try following.
sed 's/\([^_]*\)_\([^_]*\)_\([^_]*\)_\(.*\)/\4/' Input_file
Or as per Bodo's nice suggestion:
sed 's/[^_]*_[^_]*_[^_]_\(.*\)/\1/' Input_file
This might work for you (GNU sed):
sed 's/_/\n/3;s/.*\n//;t;s/Test2/\n/;s/.*\n//;t;d' file
Replace the third _ by a newline and then remove everything upto and including the first newline. If this succeeds, bail out and print the result. Otherwise, try the same method with Test2 and if this fails delete the entire line.
sed is still giving me headaches, so a little help is extremely appreciated.
In a file I have a string like:
SOME_TEXT="variables"
What I want to accomplish is to add a piece of text (variable) to either the end or the begging of the string for that text.
I tried to use variations of:
sed -i '/^SOME_TEXT="/ s/$/ SOME_TEXT="new text'/' filename
but that is failing, so clearly the quota for the string I want to add to is messing up the syntax.
LE:
A variation further is that I have a variable that I want to use as the replace in that syntax, so I have this:
sed -i "s/^SOME_TEXT="/SOME_TEXT=" $variable/" file
This actually produces this output, as it picks up incorrectly the opening/closing quotas:
SOME_TEXT = text_variable" initial text continuation
So how can I properly close the trailing quota so that I can use the variable after it?
I used
sed 's/^SOME_TEXT="/SOME_TEXT="new text/' filename
and it showed:
SOME_TEXT="new textvariables"
Is that what you want?
Escape the '"' characters with a '\' so that they don't terminate your regex string.
sed -i "s/^TEXT=\"/TEXT=\" $variable/"
I'm having issues matching strings even if they start with any number of white spaces. It's been very little time since I started using regular expressions, so I need some help
Here is an example. I have a file (file.txt) that contains two lines
#String1='Test One'
String1='Test Two'
Im trying to change the value for the second line, without affecting line 1 so I used this
sed -i "s|String1=.*$|String1='Test Three'|g"
This changes the values for both lines. How can I make sed change only the value of the second string?
Thank you
With gnu sed, you match spaces using \s, while other sed implementations usually work with the [[:space:]] character class. So, pick one of these:
sed 's/^\s*AWord/AnotherWord/'
sed 's/^[[:space:]]*AWord/AnotherWord/'
Since you're using -i, I assume GNU sed. Either way, you probably shouldn't retype your word, as that introduces the chance of a typo. I'd go with:
sed -i "s/^\(\s*String1=\).*/\1'New Value'/" file
Move the \s* outside of the parens if you don't want to preserve the leading whitespace.
There are a couple of solutions you could use to go about your problem
If you want to ignore lines that begin with a comment character such as '#' you could use something like this:
sed -i "/^\s*#/! s|String1=.*$|String1='Test Three'|g" file.txt
which will only operate on lines that do not match the regular expression /.../! that begins ^ with optional whiltespace\s* followed by an octothorp #
The other option is to include the characters before 'String' as part of the substitution. Doing it this way means you'll need to capture \(...\) the group to include it in the output with \1
sed -i "s|^\(\s*\)String1=.*$|\1String1='Test Four'|g" file.txt
With GNU sed, try:
sed -i "s|^\s*String1=.*$|String1='Test Three'|" file
or
sed -i "/^\s*String1=/s/=.*/='Test Three'/" file
Using awk you could do:
awk '/String1/ && f++ {$2="Test Three"}1' FS=\' OFS=\' file
#String1='Test One'
String1='Test Three'
It will ignore first hits of string1 since f is not true.
I am not sure why sed is not working as expected in this particular instance. I have lines of the form:
12:42:46.675 token
where I expect the timestamp to alwas have that format. Unfortunately every now and then there are lines in the file which do not begin with a timestamp and I want to get rid of those. I tried filtering out everything that does not match the above with:
sed -n /^\d{2}:\d{2}:\d{2}.\d{3}/p
but the above filters everything out, even if I give sed the -r option. What is the correct way of doing that with sed? And is there an alternative with grep?
Using grep to only display lines starting with timestamp format:
grep -E '^([0-9]{2}:){2}[0-9]{2}\.[0-9]{3} ' file
Sed doesn't accept \d, use [0-9] instead. And both { and } are not metacharacters, they are literal for sed so you will need to escape them for the special behaviour, it would result like:
sed -n '/^[0-9]\{2\}:[0-9]\{2\}:[0-9]\{2\}.[0-9]\{3\}/p' infile
EDIT: Also surround the expression between quotes (better singles than double) to avoid shell expansion.