disk size limit

[billz]

Is there any limit to the size of a disk file created by OpenFile using CVI under WindowsNT v4.0? I dump data to a file and it seems to max out at about 1.7GB. My program keeps writing, but the file does not get any bigger.

[Jeremiah Cox]

Hello Billz,
I do not know of any built-in limits imposed on files when using the CVI Formatting and I/O Library. I ran a small test here on an NT 4, Service Pack 5 machine running LabWindows/CVI 5.5.1 and was able to completely fill a 2 Gigabyte FAT-16 partition. The file size limit of FAT-16 is 2 Gigabytes. FAT-32 supports files as large as 4 Gigabytes and NTFS has no file size limit (you are only constrained by the size of the partition). As such, I do not know why your application is not writing to the file. I would suggest that you test it further and contact us if you cannot determine the source of this behavior (http://www.ni.com/ask).

Jeremiah Cox
Applications Engineer
National Instruments
http://www.ni.com/ask

[Shiner]

I did the same and created a test application that created a 2G file. I am using W2K and CVI 5.5p1 and it ran no problem. I have attached it so you can test whether its your application or a system feature...

Apart from the obvious (erm..did you have enough room on the HDD which I wouldn't dare ask), the only other possibily I could think of is that you must make sure that you close the file session after each run of the application. This also includes if the openFile is in a thread that gets terminated, since I believe that there is a finite number of file handles that can be open at anyone time.
Not knowing the size of the data that you were writing, it might have just been coincidence that the 1.7GB limit was reached?

Anyway, sorry could not be of more he
lp.

Chris