Using multiple delimiters in awk
I have a file which contain following lines:
/logs/tc0001/tomcat/tomcat7.1/conf/catalina.properties:app.env.server.name = demo.example.com
/logs/tc0001/tomcat/tomcat7.2/conf/catalina.properties:app.env.server.name = quest.example.com
/logs/tc0001/tomcat/tomcat7.5/conf/catalina.properties:app.env.server.name = www.example.com
In above output I want to extract 3 fields (Number 2, 4 and the last one *.example.com
). I am getting the following output:
cat file | awk -F'/' '{print $3 "\t" $5}'
tc0001 tomcat7.1
tc0001 tomcat7.2
tc0001 tomcat7.5
How do I also extract last field with domain name which is after '='
? How do I use multiple delimiter
to extract field?
Solution 1:
The delimiter can be a regular expression.
awk -F'[/=]' '{print $3 "\t" $5 "\t" $8}' file
Produces:
tc0001 tomcat7.1 demo.example.com
tc0001 tomcat7.2 quest.example.com
tc0001 tomcat7.5 www.example.com
Solution 2:
Good news! awk
field separator can be a regular expression. You just need to use -F"<separator1>|<separator2>|..."
:
awk -F"/|=" -vOFS='\t' '{print $3, $5, $NF}' file
Returns:
tc0001 tomcat7.1 demo.example.com
tc0001 tomcat7.2 quest.example.com
tc0001 tomcat7.5 www.example.com
Here:
-
-F"/|="
sets the input field separator to either/
or=
. -
-vOFS='\t'
is using the-v
flag for setting a variable.OFS
is the default variable for the Output Field Separator and it is set to the tab character. The flag is necessary because there is no built-in for the OFS like-F
. -
{print $3, $5, $NF}
prints the 3rd, 5th and last fields based on the input field separator.
See another example:
$ cat file
hello#how_are_you
i#am_very#well_thank#you
This file has two fields separators, #
and _
. If we want to print the second field regardless of the separator being one or the other, let's make both be separators!
$ awk -F"#|_" '{print $2}' file
how
am
Where the files are numbered as follows:
hello#how_are_you i#am_very#well_thank#you
^^^^^ ^^^ ^^^ ^^^ ^ ^^ ^^^^ ^^^^ ^^^^^ ^^^
1 2 3 4 1 2 3 4 5 6