[Lazarus] strange linux problem

[brian]

On 02/19/2014 04:07 AM, Mattias Gaertner wrote:
> On Wed, 19 Feb 2014 03:46:51 -0500
> brian <brian at meadows.pair.com> wrote:
>
>> [...]
>> on a network drive. This is using Debian 7.2, and a recent svn version
>> of Lazarus (I actually use fpcup to do the downloads and builds). The
>> information on the 'About' page is version 1.3, date 2014-02-12, fpc
>> version 2.6.3, svn revision 44027, x86_64-linux-gtk 2
>> [...]
>> chmods and/or deletes on the files on the network drive.
>> Stepping through with the debugger, some, but not all, of the
>> attempted chmods return a status of -1. Some, but not all, of the
>> calls to sysutils.deletefile return false. What is puzzling me is that
>> if, instead of calling fpchmod and sysutils.deletefile I instead call
>> fpsystem and do the operations that way, it works. I can also run up a
>> command prompt and do the failed operations that way with no problem.
>> [...]
>
> Is it reproducable on the same file?

On the basis of two examples of each, yes.

> Can you give an example file name?

Two of the files which failed to delete are unknown.mp4 and video_ts.vob.

Two files where the attempt to chmod them failed are 
The_Buddhas_Instruction_to_his_son.mp4 and 
Yogis_Of_Tibet_Rare_Documentary.mp4

In all cases, the full paths are made up of 
['A'..'Z','a'..'z','0'..'9','_'] only

(well, also '/' and '.', obviously!)


> What kind of network share?
>
It's a Western Digital 4TB "My Cloud" drive, with the shared /nfs 
directory on the drive mounted to a root-level directory on my PC.

Nobody else is using the drive - I've only two PCs on the LAN, and my 
wife's machine was switched off. The drive is hanging off one of the 
ports of my four-port Linksys router.

> Special characters, wrong encoding, server lock, faulty network.
>

Definitely not the first. I've written out the full paths to a log 
file, and they are correct - editing the logs and putting an 'ls ' in 
front of the file names provides the expected results. The drive is 
powered down overnight, and I'm the only user, so I can't see how 
there could be a server lock unless there's something wrong with the 
drive. I've seen nothing else to indicate a faulty router.


I know this all sounds crazy. I wouldn't have believed it had I not 
been seeing it for myself. The only thing I could come up with (and 
the reason for my post here) was that single-stepping under the 
debugger somehow caused the problem.

I'm not asking anybody to do any amount of research on this - it's 
trivial for me to tweak the program so that it writes commands to a 
file rather than tries to run the chmods and deletes, and I can just 
run the resulting file from the CLI.


Brian.