End of Life Ruby 3.0 has reached end of life and gets no more fixes. Switch to Ruby 4.0 →

instance method

Zlib::GzipFile#to_io

to_io

static VALUE
rb_gzfile_to_io(VALUE obj)
{
    return get_gzfile(obj)->io;
}

Same as IO.

See also #sync= #sync also in 4.1 · 4.0 · 3.4 · 3.3 · 3.2 · 3.1