I want to delete a string "www.yahoo.com" only if the line starts with assign where host.name in [ and ends with ] and also if the string is followed by comma(,) I need to delete that comma as well
assign where host.name in [ "www.google.com","www.yahoo.com","www.facebook.com" ] My output should look like
assign where host.name in [ "www.google.com", "www.facebook.com" ] I don't know how to achieve this. Kindly give me some idea about this code.
Problems like this are typically handled in sed, awk or Perl. The standard sed solution is
sed '/^assign where host.name in \[.*\]$/s/"www.yahoo.com",//' Your wording is odd. People normally don’t say
I have a pet ca followed by t.
they say
I have a pet cat.
Similarly, rather than
a string
"www.yahoo.com"… if the string is followed by comma (,)
you should just say
a string
"www.yahoo.com",
unless you mean something more complicated, like maybe
a string
"www.yahoo.com"… if the string is followed by comma (,), optionally separated by a space
in which case you should say that.
The above command does what your question asks for: it deletes the string "www.yahoo.com",. If you want to do what you showed, and what you said in a comment, add a space:
sed '/^assign where host.name in \[.*\]$/s/"www.yahoo.com",/ /' 
"www.yahoo.com" is the last entry in the list)? s/[[:space:]]*"www.yahoo.com"[[:space:]]*,\{0,1\}[[:space:]]*/ /'. But remember that ? and + aren’t defined in POSIX regular expressions.
sed) or something no less powerfull eg. Perl.assign where host.name in [is sufficient to identify the line where Yahoo is to be removed?