1 #include <u.h> 2 #include <libc.h> 3 #include "authcmdlib.h" 4 5 /* 6 * read exactly len bytes 7 */ 8 int 9 readn(int fd, char *buf, int len) 10 { 11 int m, n; 12 13 for(n = 0; n < len; n += m){ 14 m = read(fd, buf+n, len-n); 15 if(m <= 0) 16 return -1; 17 } 18 return n; 19 } 20