How to delete certain characters after a pattern using sed or awk?

Question

I have a text file containing number of lines formatted like below

001_A.wav;112.680;115.211;;;Ja. Hello; Hi:

my goal is to clean whatever is after ;;;. Meaning to delete the following characters ,;()~?

I know i can do something like sed 's/[,.;()~?,]//g'. However if I do that, it would give me something like

001_Awav112.680115211Ja Hello Hi

However I would like to delete those character only after ;;; so I would get

001_A.wav;112.680;115.211;;;Ja Hello Hi

How can I accomplish this task?

Answer 1

1st solution: Could you please try following, written and tested with shown samples in GNU awk(where assuming ;;; occurring one time in lines).

awk '
match($0,/.*;;;/){
  laterPart=substr($0,RSTART+RLENGTH)
  gsub(/[,.:;()~?]/,"",laterPart)
  print substr($0,RSTART,RLENGTH) laterPart
}'  Input_file

Explanation: Adding detailed explanation for above.

awk '                                  ##Starting awk program from here.
match($0,/.*;;;/){                     ##Using atch function to match everything till ;;; here.
  laterPart=substr($0,RSTART+RLENGTH)  ##Creating variable laterPart which has rest of the line apart from matched regex part above.
  gsub(/[,.:;()~?]/,"",laterPart)      ##Globally substituting ,.:;()~? with NULL in laterPart variable.
  print substr($0,RSTART,RLENGTH) laterPart ##Printing sub string of matched regex and laterPart var here.
}' Input_file                          ##Mentioning Input_file name here.

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2nd solution: In case you have multiple occurrences of ;;; in lines and you want to substitute characters from all fields, after 1st occurrence of ;;; then try following.

awk 'BEGIN{FS=OFS=";;;"} {for(i=2;i<=NF;i++){gsub(/[,.:;()~?,]/,"",$i)}} 1' Input_file