You can direct PL/I and C user-specified output to the same destination as the runtime output by specifying MSGFILE(SYSPRINT). In this case, PL/I and C manage their own I/O buffers, line counters, and so on, for their own user-specified output. Therefore, MSGFILE(SYSPRINT) must be used carefully because PL/I output from the PUT statement, C output from printf, and runtime output can be interspersed with one another.