Windows File Writing...

Sephiroth

OK, I just read on the MSDN that opening a file with "fopen()" and using the mode "a+" will not allow you to over-write data in a file. I have just made an MP3 tag editor, and I need to over-write data with it. I don't know the format of the encoded data, so I can't buffer the entire file to memory and then burst it into a new file, but I do know the EXACT locations of the data I want to modify. How can I do this?

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AsmGuru62

[b][red]This message was edited by AsmGuru62 at 2003-12-8 12:46:29[/red][/b][hr]
: OK, I just read on the MSDN that opening a file with "fopen()" and using the mode "a+" will not allow you to over-write data in a file. I have just made an MP3 tag editor, and I need to over-write data with it. I don't know the format of the encoded data, so I can't buffer the entire file to memory and then burst it into a new file, but I do know the EXACT locations of the data I want to modify. How can I do this?
:
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:
[code]
FILE* pFile = fopen ("any file name here", "r+b");

fseek (pFile, 1762, SEEK_SET);
// ^^^ go to exact location of 1762 bytes
// from the beginning of the file

// write a few (five symbols) bytes at this location:
fwrite ("Hello", sizeof (char), 5, pFile);
fclose (pFile);
[/code]

Sephiroth

Yeah I figured it out, but not thanks to MSDN. I have (once again) the wonder Linux MAN pages to thank. I really should just leave an SSH2 terminal open to one of my Linux-boxes 24/7 for stuff like this that M$ "forgets" to post or posts wrong. Too bad those pages don't have the Win32 GUI functions and such in them, that'd make it super-easy to find anything !
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AsmGuru62

: Yeah I figured it out, but not thanks to MSDN. I have (once again) the wonder Linux MAN pages to thank. I really should just leave an SSH2 terminal open to one of my Linux-boxes 24/7 for stuff like this that M$ "forgets" to post or posts wrong. Too bad those pages don't have the Win32 GUI functions and such in them, that'd make it super-easy to find anything !
: -[italic][b][red]S[/red][purple]e[/purple][blue]p[/blue][green]h[/green][red]i[/red][purple]r[/purple][blue]o[/blue][green]t[/green][red]h[/red][/b][/italic]
:
:
[blue]Win32 GUI? No problem...

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/winprog/winprog/functions_by_category.asp

I always post that link - super-easy to find whatever you need to find.
[/blue]

Sephiroth

: [blue]Win32 GUI? No problem...
:
: http://msdn.microsoft.com/library/default.asp?url=/library/en-us/winprog/winprog/functions_by_category.asp
:
: I always post that link - super-easy to find whatever you need to find.
: [/blue]
:
Added to favorites.

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pingpong

: Added to [b][italic]favorites[/italic][/b].

Mr Open Source is using IE!

AsmGuru62

: : Added to [b][italic]favorites[/italic][/b].
:
: Mr Open Source is using IE!
:
:
[blue]...erm... yeah, it is a free country... - I think, Seph has both in his cellar...[/blue]

Sephiroth

: : : Added to [b][italic]favorites[/italic][/b].
: :
: : Mr Open Source is using IE!
: :
: :
: [blue]...erm... yeah, it is a free country... - I think, Seph has both in his cellar...[/blue]
:
I use IE because it doesn't crash or is crappy as hell like NutScrape, and because it comes integrated into Windoze. Does all I need anyway. However, if I was a major web-guy, I'd use Opera or something. Oh wait, LONG LIVE LYNX!! If you don't get it you just don't know.

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