You're execing a single string which contain spaces and other characters that are special (the &). In that case, Perl execs a shell (with pid 22718) which then calls /opt/amber/bin/sander (with pid 22719).

Use the list form of exec instead.

In reply to Re^5: How to monitor a child process from a perl script by JavaFan
in thread How to monitor a child process from a perl script by oscarjiao

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