Replace specific character/string in specific scope with regexp

Question

e.g.

~cat ./temp
1,2,"3,1,2",4,5,"A,2,Csd",xx,a,"s,s,,",,,

After shell parse i want this output:

~parse.sh ./temp
1,2,"3_1_2",4,5,"A_2_Csd",xx,a,"s_s__",,,

i.e. replace all the , with _ in the "..." scope.

Any shell solution will be welcome, awk/sed/perl/other smart thing you can think.

snippet code the shorter the better

Answer 1

You can use this perl command line that transliterates commas to underscores for each match:

perl -pe's#"[^"]*"#$&=~y/,/_/r#ge' ./temp

$& is the whole match

y/// is the transliteration operator (it can also be written tr///)

the r modifier returns a result string (instead of the number of replaced characters).

the e modifier allows to execute code in the replacement pattern.