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 * @param argv Pointer to the arguments to pass (may be overridden)

 * @param r The current request

 * @param p The pool to allocate correct cmd/argv elements within.

 * @deffunc apr_status_t ap_cgi_build_command(const char **cmd, const char ***argv, request_rec *r, apr_pool_t *p)

 * @tip This callback may be registered by the os-specific module 

 * @remark This callback may be registered by the os-specific module 

 * to correct the command and arguments for apr_proc_create invocation

 * on a given os.  mod_cgi will call the function if registered.

 */