I have a file with many lines, in each line there is either substring
whatever_blablablalsfjlsdjf;asdfjlds;f/watch?v=yPrg-JN50sw&,whatever_blabla
or
whatever_blablabla"/watch?v=yPrg-JN50sw&" class=whatever_blablablavwhate
I want to extract a substring, like the "yPrg-JN50s" above
the matching pattern is the 11 characters after the string "/watch?="
how to extract the substring
I hope it is sed, awk in one line if not, a pn line perl script is also ok