[physfs] open for append & seek & write?

Sun Mar 30 10:47:29 EDT 2008

Hello Vaclav,

      I'd try PHYSFS_openWrite instead of PHYSFS_openAppend. I've
      never tried it though, so I don't know if when you start
      writing after you seek if it will overwrite what is there, or
      add what you wrote and shift everything else down.

      Also, I'm not sure if openWrite always forces the opened file
      to be empty or not (like fopen(x, "wb")), in which case you'd
      have to copy the original file's data into it as well.

Sunday, March 30, 2008, 9:25:03 AM, you wrote:

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VV> Date: Sun, 30 Mar 2008 15:25:03 +0200
VV> From: "Vaclav Vanc" <vanc.vaclav at gmail.com>
VV> To: physfs at icculus.org
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VV> Subject: [physfs] open for append & seek & write?
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VV> Hi  is it possible, to open existing file, seek in the middle and
VV> write something?
VV> Here is my code...

VV> #include <stdio.h>
VV> #include "physfs.h"

VV> int main(int argc, char *argv[])
VV> {
VV> char string[]="TEST";

VV> PHYSFS_init(argv[0]);
VV> PHYSFS_permitSymbolicLinks( 1 );
VV> PHYSFS_setWriteDir("./");
VV> PHYSFS_addToSearchPath( "./", 0 );

VV> PHYSFS_file *file = PHYSFS_openAppend("file.txt");

VV> PHYSFS_seek(file, 2);
VV> PHYSFS_write(file,  string, 1, 4);

VV> PHYSFS_close(file);
VV> return EXIT_SUCCESS;
VV> }

VV> It should open existing file,  seek to 2th byte from start and write 4
VV> bytes. Unfortunately these 4 bytes are written to the end of the file.
VV> What I am doing wrong?

VV> Thanks.

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Best regards,
 Indy Sams
 mailto:indy at driftsolutions.com

 P.S. This is what part of the alphabet would look like if Q & R were eliminated.