ref: 189fb3be1c27333f46853fcc68c800379348d026
dir: /libc/strncat.c/
#include <u.h>
#include <libc.h>
char*
strncat(char *s1, char *s2, long n)
{
char *os1;
os1 = s1;
while(*s1++)
;
s1--;
while(*s1++ = *s2++)
if(--n < 0)
{
s1[-1] = 0;
break;
}
return os1;
}