method

each_byte

v1_9_2_180 - Show latest stable - 0 notes - Class: IO

each_byte() public

Calls the given block once for each byte (0..255) in ios, passing the byte as an argument. The stream must be opened for reading or an IOError will be raised.

If no block is given, an enumerator is returned instead.

f = File.new("testfile")
checksum = 0
f.each_byte {|x| checksum ^= x }   #=> #<File:testfile>
checksum                           #=> 12

Show source

static VALUE
rb_io_each_byte(VALUE io)
{
    rb_io_t *fptr;
    char *p, *e;

    RETURN_ENUMERATOR(io, 0, 0);
    GetOpenFile(io, fptr);

    for (;;) {
        p = fptr->rbuf+fptr->rbuf_off;
        e = p + fptr->rbuf_len;
        while (p < e) {
            fptr->rbuf_off++;
            fptr->rbuf_len--;
            rb_yield(INT2FIX(*p & 0xff));
            p++;
            errno = 0;
        }
        rb_io_check_byte_readable(fptr);
        READ_CHECK(fptr);
        if (io_fillbuf(fptr) < 0) {
            break;
        }
    }
    return io;
}

each_byte

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