in reply to run in-program shell script under windows using cygwin
Sounds like you are using a Windows build of Perl, not a cygwin one. While cygwin knows how to execute /old/new2.sh (i.e. by looking for the shebang), Windows doesn't know anything about shebang lines (and wouldn't find /usr even if it did). Windows uses file associations to determine how to execute a non-binary.
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