ccan/ccan/foreach/_info

#include "config.h"
#include <stdio.h>
#include <string.h>

/**
 * foreach - macro for simple iteration of arrays
 *
 * The foreach_int and foreach_ptr macros allow simple iteration of
 * static arrays.  This is very efficient with good compiler support
 * (ie. gcc), and not too bad (ie. a few compares and mallocs) for
 * other compilers.
 *
 * License: LGPL (3 or any later version)
 * Author: Rusty Russell <rusty@rustcorp.com.au>
 *
 * Example:
 *	// Figure out how to get usage: message out of a program.
 *	#include <ccan/foreach/foreach.h>
 *	#include <stdio.h>
 *	#include <stdlib.h>
 *	#include <string.h>
 *	#include <err.h>
 *
 *	// Returns true if program outputs "usage:"
 *	static bool try_usage(const char *prog, const char *arg)
 *	{
 *		char *command;
 *		FILE *in;
 *		int status;
 *
 *		command = malloc(strlen(prog) + 1 + strlen(arg) + 1 +
 *				 sizeof("</dev/null 2>&1 | grep -qiw usage:"));
 *		sprintf(command, "%s %s </dev/null 2>&1 | grep -qiw usage:",
 *			prog, arg);
 *		in = popen(command, "r");
 *		if (!in)
 *			err(2, "running '%s'", command);
 *		status = pclose(in);
 *		free(command);
 *		return (WIFEXITED(status) && WEXITSTATUS(status) == 0);
 *	}
 *
 *	int main(int argc, char *argv[])
 *	{
 *		const char *arg;
 *
 *		if (argc != 2)
 *			errx(1, "Usage: %s <progname>\n"
 *			     "Figures out how to get usage message", argv[0]);
 *		foreach_ptr(arg, "--help", "-h", "--usage", "-?", "") {
 *			if (try_usage(argv[1], arg)) {
 *				printf("%s %s\n", argv[1], arg);
 *				exit(0);
 *			}
 *		}
 *		printf("%s is unhelpful\n", argv[1]);
 *		exit(1);
 *	}
 */
int main(int argc, char *argv[])
{
	if (argc != 2)
		return 1;

	if (strcmp(argv[1], "depends") == 0) {
#if !HAVE_COMPOUND_LITERALS || !HAVE_FOR_LOOP_DECLARATION
		printf("ccan/list\n");
#endif
		return 0;
	}

	return 1;
}