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instance method

IO#readchar

() -> ::String

readchar → string

static VALUE
rb_io_readchar(VALUE io)
{
    VALUE c = rb_io_getc(io);

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

Reads and returns the next 1-character string from the stream; raises EOFError if already at end-of-stream. See Character IO.

Example

f = File.open('t.txt')
f.readchar     # => "F"
f.close
File.read('t.ja') # => "こんにちは"
f = File.open('t.ja')
f.readchar.ord # => 12371
f.close

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

See also #readbyte #readline #read #readlines also in 4.0 · 3.4 · 3.3 · 3.2 · 3.1 · 3.0