STDIO_VBUF_SIZE
str->s_type.BF.s_vbuf = safe_realloc(NULL, STDIO_VBUF_SIZE);
STDIO_VBUF_SIZE) != 0) {
str->s_buffer = xzmap(0, STDIO_VBUF_SIZE, PROT_READ |
str->s_buffer_size = STDIO_VBUF_SIZE;