slow.c

#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>

#include "arg.h"

char *argv0;

static void usage(void);

void
usage()
{
	fprintf(stderr, "usage: %s [-t usec] [-f]\n", argv0);
	exit(1);
}

int
main(int argc, char *argv[])
{
	char            buffer;
	size_t          nread;
	useconds_t      useconds        = 1000000; // default 1 second
	unsigned int    flush           = 0;

	ARGBEGIN {
	case 't':
		useconds = atoi(EARGF(usage()));
		break;
	case 'f':
		flush = 1;
		break;
	default:
		usage();
	} ARGEND;

	while ((nread = fread(&buffer, 1, sizeof buffer, stdin)) > 0) {
		usleep(useconds);

		if (fwrite(&buffer, 1, nread, stdout) != nread) {
			fprintf(stderr, "stdout: write error");
			exit(1);
		}

		if (flush)
			fflush(stdout);
	}

	if (ferror(stdin)) {
		fprintf(stderr, "stdin: read error");
		exit(1);
	}

	return 0;
}