Re: file:write() fails silently for read-only files

[Josh Simmons <simmons.44@...>]

On Tue, Sep 6, 2011 at 5:09 PM, HyperHacker <hyperhacker@gmail.com> wrote:
> On Tue, Sep 6, 2011 at 00:51, Josh Simmons <simmons.44@gmail.com> wrote:
>> On Tue, Sep 6, 2011 at 4:39 PM, HyperHacker <hyperhacker@gmail.com> wrote:
>>> Lua 5.1.4  Copyright (C) 1994-2008 Lua.org, PUC-Rio
>>>> f=io.open('foo.foo', 'r')
>>>> f:write('ffd')
>>>> f:close()
>>>>
>>>
>>> Call me crazy, but I feel like f:write() should throw an error when
>>> trying to write to a read-only file, instead of just doing nothing.
>>>
>>> --
>>> Sent from my toaster.
>>>
>>>
>>
>> Check the return value of write.
>>
>>
>
> I get "bad file descriptor" which seems rather misleading. No return
> value is documented in the manual though.
>
> --
> Sent from my toaster.
>
>

Odd that it's not mentioned.

All IO functions use the luaL_fileresult function however, which uses
errno+strerror to report any error message and so the actual error
message is outside Lua's control.