TYPE leaves the file open

[vefatica]

I'm probably not supposed to TYPE a 4GB binary file, but I tried to do so, redirecting output to NUL, and found that the file was left open. I was trying to get Windows to cache the file.

d:\projects2022\crc32\x64\release> d 4g
2024-01-08  23:07   4,294,967,296  4g

d:\projects2022\crc32\x64\release> filelock 4g

d:\projects2022\crc32\x64\release> type 4g > nul
d:\projects2022\crc32\x64\release> filelock 4g
 8924  D:\tc31\tcc.exe

 

[Alpengreis]

Is that also the case with cmd type?

 

[vefatica]

Is that also the case with cmd type?

No. I only tried once. And I figure CMD actually did it (judging by how much time it took, 66 sec). TCC fails the first time in 4 sec. and, on subsequent tries, immediately.

 

[Alpengreis]

JFI: to cache a file, a "simple" MD5 hash for the file could be faster than a type ...

 

[rconn]

TYPE is (and always has been) limited to 4Gb files (because, why would you??). The problem with allowing > 4Gb files is several Windows APIs that TYPE uses don't support it, and it would break FTP / HTTP files, and pipes.

 

[vefatica]

I wann't asking that it handle > 4Gb files, only suggesting that it didn't leave them locked when it fails.

 

[rconn]

It's the RTL doing that, not my code. I will have to rewrite a couple of the RTL functions, so probably 200-300 lines of code. Since nobody had noticed it for the last 30 years, it won't get a very high priority for an immediate fix.

You can request it in the Suggestions Forum.

 

[JohnQSmith]

You can request it in the Suggestions Forum.

...or you could add it to your reported bugs list.

 

[rconn]

...or you could add it to your reported bugs list.

The file being left open is a bug (sort of, though it's a Windows bug, not TCC). The part about wanting to TYPE a > 4Gb binary file would be a feature request. (Or not, since the OP didn't actually mean to do it.)

 

[JohnQSmith]

The part about wanting to TYPE a > 4Gb binary file would be a feature request.

Point taken.