jos/user/cat.c

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2018-10-24 17:44:45 -07:00
#include <inc/lib.h>
char buf[8192];
void
cat(int f, char *s)
{
long n;
int r;
while ((n = read(f, buf, (long)sizeof(buf))) > 0)
if ((r = write(1, buf, n)) != n)
panic("write error copying %s: %e", s, r);
if (n < 0)
panic("error reading %s: %e", s, n);
}
void
umain(int argc, char **argv)
{
int f, i;
binaryname = "cat";
if (argc == 1)
cat(0, "<stdin>");
else
for (i = 1; i < argc; i++) {
f = open(argv[i], O_RDONLY);
if (f < 0)
printf("can't open %s: %e\n", argv[i], f);
else {
cat(f, argv[i]);
close(f);
}
}
}