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#include <errno.h>
#include <stdio.h>
#include <stdarg.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <fcntl.h>

#include "panic.h"


void cat(int fd, char * name)
{
	char buffer[4096];
	ssize_t length;
	while (0 < (length=read(fd, buffer, sizeof(buffer))))
		if (length != write(1, buffer, length))
			panic("write: %s: %s", name, strerror(errno));
	if (0 > length)
		panic("read: %s: %s", name, strerror(errno));
}


int main(int argc, char * argv[])
{
	int i;
	int fd;
	if (1 == argc)
		cat(0, "<stdin>");
	else for (i = 1; i < argc; ++i)
	{
		fd = open(argv[i], O_RDONLY);
		if (0 > fd)
			panic("open: %s: %s", argv[i], strerror(errno));
		else
		{
			cat(fd, argv[i]);
			close(fd);
		}
	}
}