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instance method

IO#rewind

() -> ::Integer

rewind → 0

static VALUE
rb_io_rewind(VALUE io)
{
    rb_io_t *fptr;

    GetOpenFile(io, fptr);
    if (io_seek(fptr, 0L, 0) < 0 && errno) rb_sys_fail_path(fptr->pathv);
    if (io == ARGF.current_file) {
        ARGF.lineno -= fptr->lineno;
    }
    fptr->lineno = 0;
    if (fptr->readconv) {
        clear_readconv(fptr);
    }

    return INT2FIX(0);
}

Repositions the stream to its beginning, setting both the position and the line number to zero; see Position and Line Number:

Example

f = File.open('t.txt')
f.tell     # => 0
f.lineno   # => 0
f.gets     # => "First line\n"
f.tell     # => 12
f.lineno   # => 1
f.rewind   # => 0
f.tell     # => 0
f.lineno   # => 0
f.close

Note that this method cannot be used with streams such as pipes, ttys, and sockets.

See also #reopen #scroll_backward #readpartial #scroll_forward also in 4.0 · 3.4 · 3.3 · 3.2 · 3.1 · 3.0

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