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instance method

IO#readbyte

readbyte → integer

static VALUE
rb_io_readbyte(VALUE io)
{
    VALUE c = rb_io_getbyte(io);

    if (NIL_P(c)) {
        rb_eof_error();
    }
    return c;
}

Reads and returns the next byte (in range 0..255) from the stream; raises EOFError if already at end-of-stream. See Byte IO.

Example

f = File.open('t.txt')
f.readbyte # => 70
f.close
f = File.open('t.rus')
f.readbyte # => 209
f.close

Related: IO#getbyte (will not raise EOFError).

See also #read #readchar #raw! #readline also in 4.1 · 4.0 · 3.4 · 3.3 · 3.1 · 3.0