When writing output to a standard stream from a C to C++ ILC application, both the C and C++ code should use the C I/O functions such as printf and puts, which allow the output to be written in the expected order. If your C++ program is directing output to cout (the default), you may get output in an unexpected order. See z/OS XL C/C++ Programming Guide chapter on IOSTREAMS for further information.

There is no restriction on passing file pointers from C to C++; a file opened using fopen in a C program may be closed by using fclose in a C++ program, and vice versa.