Turn a C string with NULL bytes into a char array

Question

I am using GetOpenFileName with multiple select capabilities. The files picked are returned in a LPSTR. Inside this LPSTR, the files selected are separated by NULL bytes. I want to split the LPSTR into an array and then loop over that array.

In PHP I would do:

 $array = explode("\0", $string);

But since I am new to C, I have no idea what I am doing.

Answer 1

You could do this to loop through the strings:

char *Buffer;             // your null-separated strings
char *Current;            // Pointer to the current string
// [...]
for (Current = Buffer; *Current; Current += strlen(Current) + 1)
  printf("GetOpenFileName returned: %s\n", Current);

You can adapt this code to create arrays if it's really necessary.

Answer 2

Would a string copy do the trick for you?

LPSTR ptrFileName;
char buf[100];
strcpy(buf, ptrFileName);
/* Now iterate */
for (int nLoopCnt = 0; nLoopCnt < (sizeof(buf) / sizeof(buf[0])); nLoopCnt++){
   char ch = buf[nLoopCnt];
   /* Do whatever with ch */
}

Hope this helps, Best regards, Tom.

Answer 3

The easiest thing to do is probably just to loop over the returned strings directly. (There's no need to create a separate array.) The code would look something like this (error checking omitted):

GetOpenFileName( &ofn );

LPSTR pszFileName = ofn.lpstrFile;

while( *pszFileName != 0 )
{
    // do stuff...
    pszFileName += strlen( pszFileName ) + 1;
}

Also, don't forget that if the user selects multiple files, the first entry will be the folder name.