ref: af25b58d05b0700990057ce3f8c853bd43f2ece0
dir: /lib/c/stdio/_allocbuf.c/
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include "../libc.h"
int
_allocbuf(FILE *fp)
{
	char *bp;
	if ((bp = malloc(BUFSIZ)) == NULL) {
		fp->flags |= _IOERR;
		errno = ENOMEM;
		return EOF;
	}
	fp->len = BUFSIZ;
	fp->rp = fp->wp = fp->buf = bp;
	fp->lp = bp + BUFSIZ;
	return 0;
}