The project has a requirement to replace some strings with special characters in the file, such as
Sample file - sample input
file.conf
bridge.mqtt.aws.mountpoint = aws/
bridge.mqtt.aws.certfile = etc/certs/client-cert.pem
sed command one
i type sed command as follows
sed -i "s/aws/test/g" ./file.conf
result one
The results are as follows
bridge.mqtt.test.mountpoint = test/
# The line I would expect would be `bridge.mqtt.test.mountpoint = aws/`
bridge.mqtt.test.certfile = etc/certs/client-cert.pem
I knew I could delete g to match the first one per line, but I worry that there are multiple places in a row that need to be matched.
sed command two
So, I use an elongated string match, the sed command as follows
sed -i "s/.aws./.test./g" ./file.conf,
result two
which failed as follows
bridge.mqtt.test.mountpoint =.test.
# The line I would expect would be `bridge.mqtt.test.mountpoint = aws/`
bridge.mqtt.test.certfile = etc/certs/client-cert.pem
How can I modify the sed instruction to achieve the effect I want
desired output
Use a command like sed command two to get the following results
sed
bridge.mqtt.test.mountpoint = aws/
bridge.mqtt.test.certfile = etc/certs/client-cert.pem
You say that removing g will not work, but all examples that you have given will work as expected. You have not provided any counter examples which would not yield the expected result, so my answer is based on the assumption that you only want to replace "aws" if it is preceded by a period:
sed -i 's/\.aws/.test/g' ./file.conf
This of course will not work, if the part after the = character contains a period too.
Input:
bridge.mqtt.aws.mountpoint = aws/
bridge.mqtt.aws.certfile = etc/certs/client-cert.pem
Output:
bridge.mqtt.test.mountpoint = aws/
bridge.mqtt.test.certfile = etc/certs/client-cert.pem
Will not work with input:
bridge.mqtt.aws.mountpoint = /hidden/dir/.aws/
resulting in:
bridge.mqtt.test.mountpoint = /hidden/dir/.test/
But maybe the provided solution is already good enough™ for your input set.
Note that something like "aws123" will also be replaced with "test123", which might or not might be what you want to do.
More ideas
If you don't mind running the "cleanup script" multiple times in a row (e.g. is there still something to replace? -> run sed), you could do the following to only replace "aws" there's no = character before it):
sed 's/^\([^=]*\)\.aws/\1.test/g'
Related
An input file is given, each line of which contains delimited data with extra delimiter at the end in data/header with or without enclosures.
Extra delimiter at the end it can contain with/without spaces.
Scenario 1 : Header & Data contain extra delimiter at the end
eno|ename|address|
A|B|C|
D|E|F|
Scenario 2 : Header doesn't contain extra delimiter at the end
eno|ename|address
A|B|C|
D|E|F|
Scenario 3 : With enclosures
eno|ename|address|
1|2|"A"|
Final output has to be like
Scenario 1 :
eno|ename|address
A|B|C
D|E|F
Scenario 2 :
eno|ename|address
A|B|C
D|E|F
Scenario 3 :
eno|ename|address
1|2|"A"
Solution which i have tried so far. But below solution won't work for all three scenarios is there anyway which i can make single command to support all the three scenarios in Sed/Awk/Perl
perl -pne 's/(.*)\|/$1/' filename
Could you please try following.
awk '{gsub(/\|$|\| +$/,"")} 1' Input_file
Explanation:
gsub is awk function which Globally substitute matched pattern with mentioned value.
Explanation of regex:
/\|$|\| +$/: Here there are 2 parts of regex. First is /\|$ and second is +$ which is segrigated with | where 1st regex is for removing | from last of the line and second regex removes | with space at last. So it basically takes care of both conditions successfully.
perl -lpe 's/\|\s*$//' file
will do it. That only removes pipes followed by optional whitespace at the end of each line. Note the $ line anchor.
I added the -l since each line's newline will get removes by the s/// command, and -l will put it back.
All you need is this:
sed 's/|$//'
A bit more generic. Let's assume you have the same problem, but with different field separators in different files. Some of these field separators are regular expressions (e.g. a sequence of blanks), others are just a single character c. With a tiny little awk program you can get far:
# remove_last_empty_field.awk
# 1. Get the correct `fs`
BEGIN { fs=FS; if(length(FS)==1) fs=(FS==" ") ? "[[:blank:]]+" : "["FS"]" }
# remove the empty field
{ sub(fs"$","") }
# Print the current record
1
Now you can run this on your various files as:
$ awk -f remove_last_empty_field.awk f1.txt
$ awk -f remove_last_empty_field.awk FS="|" f2.txt
$ awk -f remove_last_empty_field.awk FS="[|.*]" f3.txt
perl -pi -e 's/\|$//' Your_FIle
I'm trying to extract the name of the file name that has been generated by a Java program. This Java program spits out multiple lines and I know exactly what the format of the file name is going to be. The information text that the Java program is spitting out is as follows:
ABCASJASLEKJASDFALDSF
Generated file YANNANI-0008876_17.xml.
TDSFALSFJLSDJF;
I'm capturing the output in a variable and then applying a sed operator in the following format:
sed -n 's/.*\(YANNANI.\([[:digit:]]\).\([xml]\)*\)/\1/p'
The result set is:
YANNANI-0008876_17.xml.
However, my problem is that want the extraction of the filename to stop at .xml. The last dot should never be extracted.
Is there a way to do this using sed?
Let's look at what your capture group actually captures:
$ grep 'YANNANI.\([[:digit:]]\).\([xml]\)*' infile
Generated file YANNANI-0008876_17.xml.
That's probably not what you intended:
\([[:digit:]]\) captures just a single digit (and the capture group around it doesn't do anything)
\([xml]\)* is "any of x, m or l, 0 or more times", so it matches the empty string (as above – or the line wouldn't match at all!), x, xx, lll, mxxxxxmmmmlxlxmxlmxlm, xml, ...
There is no way the final period is removed because you don't match anything after the capture groups
What would make sense instead:
Match "digits or underscores, 0 or more": [[:digit:]_]*
Match .xml, literally (escape the period): \.xml
Make sure the rest of the line (just the period, in this case) is matched by adding .* after the capture group
So the regex for the string you'd like to extract becomes
$ grep 'YANNANI.[[:digit:]_]*\.xml' infile
Generated file YANNANI-0008876_17.xml.
and to remove everything else on the line using sed, we surround regex with .*\( ... \).*:
$ sed -n 's/.*\(YANNANI.[[:digit:]_]*\.xml\).*/\1/p' infile
YANNANI-0008876_17.xml
This assumes you really meant . after YANNANI (any character).
You can call sed twice: first in printing and then in replacement mode:
sed -n 's/.*\(YANNANI.\([[:digit:]]\).\([xml]\)*\)/\1/p' | sed 's/\.$//g'
the last sed will remove all the last . at the end of all the lines fetched by your first sed
or you can go for a awk solution as you prefer:
awk '/.*YANNANI.[0-9]+.[0-9]+.xml/{print substr($NF,1,length($NF)-1)}'
this will print the last field (and truncate the last char of it using substr) of all the lines that do match your regex.
I want to insert a range of lines from a file, say something like 210,221r before the first occurrence of a pattern in a bunch of other files.
As I am clearly not a GNU sed expert, I cannot figure how to do this.
I tried
sed '0,/pattern/{210,221r file
}' bunch_of_files
But apparently file is read from line 210 to EOF.
Try this:
sed -r 's/(FIND_ME)/PUT_BEFORE\1/' test.text
-r enables extendend regular expressions
the string you are looking for ("FIND_ME") is inside parentheses, which creates a capture group
\1 puts the captured text into the replacement.
About your second question: You can read the replacement from a file like this*:
sed -r 's/(FIND_ME)/`cat REPLACEMENT.TXT`\1/' test.text
If replace special characters inside REPLACEMENT.TXT beforehand with sed you are golden.
*= this depends on your terminal emulator. It works in bash.
In https://stackoverflow.com/a/11246712/4328188 CodeGnome gave some "sed black magic" :
In order to insert text before a pattern, you need to swap the pattern space into the hold space before reading in the file. For example:
sed '/pattern/ {
h
r file
g
N
}' in
However, to read specific lines from file, one may have to use a two-calls solution similar to dummy's answer. I'd enjoy knowing of a one-call solution if it is possible though.
I have a file with a lot of text, but I want to print only words that contain "#" at the beginning. Ex:
My name is #Laura and I live in #London. Name=#Laura. City=#London
How can I print all words that start with #?.I did this the following and it worked, but I want to do it using sed. I tried several patters, but I cannot make it print anything.
grep -o -E "#\w+" file.txt
Thanks
Use this sed command:
sed 's/[^#]*\(#[^ .]*\)/\1\n/g' file.txt
Explanation: we invoke the substitution command of sed. This has following structure: sed 's/regex/replace/options'. We will search for a regex and replace it using the g option. g makes sure the match is made multiple times per line.
We look for a series of non at chars followed by an # and a number of non-spaces #[^ ]*. We put this last part in a group \(\) and sub it during the replacement \1.
Note that we add a newline at the end of each match, you can also get the output on a single line by omitting the \n.
I'm trying to extract a list of CentOS domain names only from http://mirrorlist.centos.org/?release=6.4&arch=x86_64&repo=os
Truncating prefix "http://" and "ftp://" to the first "/" character only resulting a list of
yum.phx.singlehop.com
mirror.nyi.net
bay.uchicago.edu
centos.mirror.constant.com
mirror.teklinks.com
centos.mirror.netriplex.com
centos.someimage.com
mirror.sanctuaryhost.com
mirrors.cat.pdx.edu
mirrors.tummy.com
I searched stackoverflow for the sed method but I'm still having trouble.
I tried doing this with sed
curl "http://mirrorlist.centos.org/?release=6.4&arch=x86_64&repo=os" | sed '/:\/\//,/\//p'
but doesn't look like it is doing anything. Can you give me some advice?
Here you go:
curl "http://mirrorlist.centos.org/?release=6.4&arch=x86_64&repo=os" | sed -e 's?.*://??' -e 's?/.*??'
Your sed was completely wrong:
/x/,/y/ is a range. It selects multiple lines, from a line matching /x/ until a line matching /y/
The p command prints the selected range
Since all lines match both the start and end pattern you used, you effectively selected all lines. And, since sed echoes the input by default, the p command results in duplicated lines (all lines printed twice).
In my fix:
I used s??? instead of s/// because this way I didn't need to escape all the / in the patterns, so it's a bit more readable this way
I used two expressions with the -e flag:
s?.*://?? matches everything up until :// and replaces it with nothing
s?/.*?? matches everything from / until the end replaces it with nothing
The two expressions are executed in the given order
In modern versions of sed you can omit -e and separate the two expressions with ;. I stick to using -e because it's more portable.