Thread: Dynamic Structure Array Size

Hi, I'm in need of help getting my code to create a dynamic structure array based on the number of files. Here is the code.

Code:

#include <stdio.h>
struct Version
{
       int major;
       int minor;
       int build;
       
       int numFiles;
};

struct Download
{
       char name[56];
       char outName[16];
};

int main()
{
    struct Version ver;
    int j;
    
    ver.major = 0;
    ver.minor = 4;
    ver.build = 2;
    
    ver.numFiles = 1;
    
    struct Download file[ver.numFiles];
    
    file[0].name[] = "http://website.com/projects/dod/Files.rar";
    file[0].outName[] = "Files.rar";
    
    FILE *fp;
    
    fp = fopen("version.dat", "wb");
    
    fwrite(&ver, 1, sizeof(ver), fp);
    
    fclose(fp);
    
    ver.minor = 5;
    
    fp = fopen("update.dat", "wb");
    
    fwrite(&ver, 1, sizeof(ver), fp);
    fwrite(&file, 1, sizeof(file), fp);
    
    fclose(fp);
    
    sleep(100);
    
    fp = fopen("version.dat", "rb");
    
    fread(&ver, sizeof(ver), 1, fp);
    
    fclose(fp);
    
    printf("Version.dat\n\nVersion %i.%i.%i Number of files %i\n\n", ver.major, ver.minor, ver.build, ver.numFiles);
    
    fp = fopen("update.dat", "rb");
    
    fread(&ver, sizeof(ver), 1, fp);
    fread(&file[ver.numFiles], sizeof(file[ver.numFiles]), 1, fp);
    
    fclose(fp);
    
    printf("Update.dat\n\nVersion %i.%i.%i Number of files %i\n\n", ver.major, ver.minor, ver.build, ver.numFiles);
    for(j = 0; j < ver.numFiles; j++)
    printf("Name %s\nOutName %s\n\n", file[j].name, file[j].outName);
    
    getchar();
    return 0;
}

What this program (is suppose to) does is:

1. Creates a version.dat to contain the version information (numFiles is useless for this file)
2. Creates an updated.dat file to contain the new file version, the number of files needed to download, and finally the path to the file(s), and the outfilename(s).
3. Read in this data, and display it to the screen

Thanks for the help

You cannot use the assignment operator for a string except at declaration time.

Code:

file[0].name[] = "http://website.com/projects/dod/Files.rar";file[0].outName[] = "Files.rar";

use strcpy()

If you want dynamic allocation at runtime, you should look at malloc() and free() and start thinking about pointers to structs.

Ok, well i got it working w/ strcpy. But strcpy does what i need, so i won't need malloc. thanks.