explainshell.com - grep.1posix -E %27%28%5EINT%7C%5EEXT%29%27 Script.txt %7C nl %7C sed -E -e %27s%2F%28%5B0-9%5D%2B%29.%2F%5C1%2C%2F%27 -e %27s%2F%28INT%7CEXT%29.%7B0%2C2%7D%2F%5C1%2C%2F%27 %3E SceneList.csv

-E %27%28%5EINT%7C%5EEXT%29%27 Script.txt %7C nl %7C sed -E -e %27s%2F%28%5B0-9%5D%2B%29.%2F%5C1%2C%2F%27 -e %27s%2F%28INT%7CEXT%29.%7B0%2C2%7D%2F%5C1%2C%2F%27 %3E SceneList.csv

search a file for a pattern

-E     Match using extended regular expressions. Treat each pattern specified as an ERE, as described  in
       the  Base  Definitions  volume of IEEE Std 1003.1-2001, Section 9.4, Extended Regular Expressions.
       If any entire ERE pattern matches some part of an input line excluding the terminating  <newline>,
       the line shall be matched.  A null ERE shall match every line.