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Passing char * to function and populating inside

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Passing char * to function and populating inside

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Join Date: Feb 2005

Posts: 464

Reputation: winbatch is on a distinguished road

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Solved Threads: 18

winbatch

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**Passing char * to function and populating inside**

Jul 27th, 2005

Here's what I'm trying to do:

create an empty/NULL char * in one place, pass it to a function who will populate it (and tell me the size), and then use the char * elsewhere. However, when I get out of the function..

Here's the function that expects the char * and attempts to populate it:

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bool FileUtilities::loadFullFileBinary( const string &filename, char * fileContents, long & sizeOfContents )
 
{
 
FILE *file = fopen(filename.c_str(), "rb");
 
if ( !file )
 
returnfalse;
 
 
 
 
 
fseek(file, 0, SEEK_END);
 
sizeOfContents = ftell(file);
 
cout<<"SIZE:"<<sizeOfContents<<endl;
 
rewind(file);
 
fileContents = newchar[sizeOfContents];
 
if ( fileContents )
 
{
 
if ( !fread(fileContents, sizeOfContents, 1, file) == 1 )
 
{
 
//puts(buffer);
 
delete [] fileContents;
 
sizeOfContents=0;
 
returnfalse;
 
}
 
}
 
fclose(file);
 
returntrue;
 
}

Here's the code (assume in main()) trying to use it.

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char * me=NULL;
 
long size;
 
bool status = FileUtilities::loadFullFileBinary("test.txt", me, size );
 
if ( !status )
 
throw DHException(*this, "Couldn't read file" );
 
else
 
{
 
multiLog.writeLog( "SIZE WAS '%ld'", size );
 
if ( me != NULL )
 
{
 
cout<<"TEST:"<<me[0]<<endl;
 
cout<<"TEST:"<<me[1]<<endl;
 
}
 
else
 
cout<<"WAS NULL"<<endl;
 
 
 
}

I am finding that the char * is populated inside the function (loadFullFileBinary) but when I attempt to look at it after the function has returned, it is null... What am I doing wrong? (You can ignore the DHException and multiLog bit, they are not related to the problem...)

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Passing char * to function and populating inside

Passing char * to function and populating inside

Passing char * to function and populating inside

**Passing char * to function and populating inside**