U_RECNUM(SEXP) (INTEGER)

 Function
  Determine if a user is registered on the system and what the record
  number (0-65535) is.

 Syntax
  U_RECNUM(user)

   user = A string expression with the user name to search for.

 Return Type & Value
  INTEGER
  Returns the record number of the user in the USERS file if found
  or -1 if not found.

 Remarks
  This function serves two purposes.  The first is to determine whether or
  not a given user name is registered on the system.  If the value -1 is
  returned the user isn't in the user files.  The second use is to get the
  users record number for the U_INCONF() function to determine whether or
  not a user is registered in a given conference.

 Examples
  INTEGER i,rec
  STRING  un,ynStr(1)
  LET ynStr(0) = "NO"
  LET ynStr(1) = "YES"
  INPUT "User name",un
  NEWLINE
  LET rec = U_RECNUM(un)
  FOR i = 1 TO 10
    PRINTLN un," in conf ",i,":  ",ynStr(U_INCONF(i,rec))
  NEXT