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Top Forums Programming [c] How to calculate size of the file from size of the buffer? Post 302656147 by jim mcnamara on Thursday 14th of June 2012 09:55:10 AM
Old 06-14-2012
It is not guaranteed to work. Use stat() to get a file size.
Code:
#include <sys/stat.h>
size_t filesize(int fd)
{
     struct stat st;
     if(fstat(fd, &st) == -1 )
     {
          perror("cannot stat file");
          exit(1);
      }
     return st.st_size;
}

void myfoo(void)
{
    size_t bytes;
    //.......... your code here
     bytes=filesize(fileno(fic_sortie));
    //.......  more code here
}

try something like that.
 

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FILESIZE(3)								 1							       FILESIZE(3)

filesize - Gets file size

SYNOPSIS
int filesize (string $filename) DESCRIPTION
Gets the size for the given file. PARAMETERS
o $filename - Path to the file. RETURN VALUES
Returns the size of the file in bytes, or FALSE (and generates an error of level E_WARNING) in case of an error. Note Because PHP's integer type is signed and many platforms use 32bit integers, some filesystem functions may return unexpected results for files which are larger than 2GB. EXAMPLES
Example #1 filesize(3) example <?php // outputs e.g. somefile.txt: 1024 bytes $filename = 'somefile.txt'; echo $filename . ': ' . filesize($filename) . ' bytes'; ?> ERRORS
/EXCEPTIONS Upon failure, an E_WARNING is emitted. NOTES
Note The results of this function are cached. See clearstatcache(3) for more details. Tip As of PHP 5.0.0, this function can also be used with some URL wrappers. Refer to "Supported Protocols and Wrappers" to determine which wrappers support stat(3) family of functionality. SEE ALSO
file_exists(3). PHP Documentation Group FILESIZE(3)
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