VMS Help System Services, $WAITFR  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    Tests a specific event flag and returns immediately if the flag
    is set; otherwise, the process is placed in a wait state until
    the event flag is set.

    Format

      SYS$WAITFR  efn

    C Prototype

      int sys$waitfr  (unsigned int efn);

  Additional Information (explode) :

• Argument