Re: file truncate not working on 128GB file in Windows

Hard to tell...

Apparently you didn't

check the return code
didn't use seek beforehand
didn't tell us if an exception occured

From truncate

truncate FILEHANDLE,LENGTH truncate EXPR,LENGTH Truncates the file opened on FILEHANDLE, or named by EXPR, to the specified length. Raises an exception if truncate isn't implemented on your system. Returns true if successful, undef on error. The behavior is undefined if LENGTH is greater than the length of the file. The position in the file of FILEHANDLE is left unchanged. You may want to call seek before writing to the file. Portability issues: "truncate" in perlport.

> I tried to write this same code in other languages, and those codes failed too

Probably a problem for Windows XP (!) to handle a Linux FS.

So not really a Perl problem.

Cheers Rolf
_{(addicted to the Perl Programming Language :)

see Wikisyntax for the Monastery}

Comment on Re: file truncate not working on 128GB file in Windows

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Re^2: file truncate not working on 128GB file in Windows by bliako (Abbot) on Feb 06, 2024 at 11:17 UTC
`... to handle a Linux FS.` [download] it's just a binary file	[reply] [d/l]
Re^2: file truncate not working on 128GB file in Windows by harangzsolt33 (Deacon) on Feb 06, 2024 at 05:47 UTC
That explains something. I didn't realize that truncate returns undef if it fails. I thought it was supposed to return a zero or empty string. Oh, well, it's in the manual. Doh! Why didn't I see that? Anyway, I thought that was weird. I wonder what's the limit where truncate will not fail. I know that earlier versions of Windows XP before Service Pack 2 had a limitation of 120GB. They couldn't access physical storage space above the 120gb limit, which is also really unexplainable. weird. Well, I think, it's time for me to transition to Linux. I've used Windows all my life, but it's becoming increasingly uncomfortable and I have to live with so many limitations...	[reply]
Re^3: file truncate not working on 128GB file in Windows by LanX (Saint) on Feb 07, 2024 at 04:21 UTC
Did you see perlport#truncate ? > (Win32) If a FILEHANDLE is supplied, it must be writable and opened in append mode (i.e., use `open(my $fh, '>>', 'filename')` or `sysopen(my $fh, ..., O_APPEND\|O_RDWR).` If a filename is supplied, it should not be held open elsewhere. Probably that's an indication what's going wrong with TinyPerl. And are you sure the file isn't opened otherwise? Cheers Rolf _{(addicted to the Perl Programming Language :) see Wikisyntax for the Monastery}	[reply] [d/l] [select]