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#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 (v3 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;
}
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