#include <u.h>#include <libc.h>#include <bio.h>#include "authcmdlib.h" intreadarg(int fd, char *arg, int len){	char buf[1];	int i; 	i = 0;	memset(arg, 0, len);	while(read(fd, buf, 1) == 1){		if(i < len - 1)			arg[i++] = *buf;		if(*buf == '\0'){			arg[i] = '\0';			return 0;		}	}	return -1;}