xv6/cat.c

40 lines
684 B
C

#include "types.h"
#include "stat.h"
#include "user.h"
char buf[512];
void cat(int fd) {
int n;
while ((n = read(fd, buf, sizeof(buf))) > 0) {
if (write(1, buf, n) != n) {
printf(1, "cat: write error\n");
exit();
}
}
if (n < 0) {
printf(1, "cat: read error\n");
exit();
}
}
int main(int argc, char *argv[]) {
int fd, i;
if (argc <= 1) {
cat(0);
exit();
}
for (i = 1; i < argc; i++) {
if ((fd = open(argv[i], 0)) < 0) {
printf(1, "cat: cannot open %s\n", argv[i]);
exit();
}
cat(fd);
close(fd);
}
exit();
}