Example: Get a stream to override a file in r/w, sync

public static int main (string[] args) {
if (args.length != 2) {
print ("%s FILE\n", args[0]);
return 0;
}

try {
File file = File.new_for_commandline_arg (args[1]);
FileIOStream iostream = file.replace_readwrite (null, false, FileCreateFlags.NONE);

OutputStream ostream = iostream.output_stream;
DataOutputStream dostream = new DataOutputStream (ostream);
dostream.put_string ("my-line\n");
} catch (Error e) {
print ("Error: %s\n", e.message);
}

return 0;
}

 valac --pkg gio-2.0 GLib.File.replace_readwrite.vala

See: