Cygwin API Reference
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cygwin_winpid_to_pid

extern "C" pid_t cygwin_winpid_to_pid (int winpid);

Given a windows pid, converts to the corresponding Cygwin pid, if any. Returns -1 if windows pid does not correspond to a cygwin pid.

Example 2-3. Example use of cygwin_winpid_to_pid

      extern "C" cygwin_winpid_to_pid (int winpid);
      pid_t mypid;
      mypid = cygwin_winpid_to_pid (windows_pid);
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