#include <u.h>#include <libc.h>#include <bio.h>#include "String.h" /* Append an input line to a String. * * Returns a pointer to the character string (or 0). * Trailing newline is left on. */ extern char *s_read_line(Biobuf *fp, String *to){	char *cp;	int llen; 	if(to->ref > 1)		sysfatal("can't s_read_line a shared string");	s_terminate(to);	cp = Brdline(fp, '\n');	if(cp == 0)		return 0;	llen = Blinelen(fp);	if(to->end - to->ptr < llen)		s_grow(to, llen);	memmove(to->ptr, cp, llen);	cp = to->ptr;	to->ptr += llen;	s_terminate(to);	return cp;}