If your main() function uses the standard argc and argv arguments, the Metal C initialization routine is called to parse the raw parameter data received from the hosting environment and to convert the parameter to the standard argc and argv format. If your program is not invoked in the z/OS® UNIX System Services (USS) environment, you can use the ARGPARSE or NOARGPARSE options to determine if the EXEC PARM needs to be further parsed into individual arguments; the EXEC PARM has to be in this format: a halfword length field followed by a maximum of 100 characters where the length field contains a binary count of the number of bytes in the PARM field. For more information about the ARGPARSE option, see z/OS XL C/C++ User's Guide.
If your main() function uses argc and argv arguments and you do not want the parsing to be performed, you can set the new Global Set Symbol &CCN_APARSE to 0 in your prolog code to conditionally bypass the argument parsing. For detailed information, see Table 2.