Question

I have the following data structure:

struct file{
    char  name[MAX_FILE_NAME];
    char  data[BLOCK_SIZE - MAX_FILE_NAME]
};

struct disk{
    vector<file> current_file;
};

When I try to modify something say in index 0 of whatever disk I’ve created like so:

disk new_disk;

new_disk.current_file[0].name = "new name";

I get the error that expression must be a modifiable |value

I feel like it’s late and I just can’t seem to understand something simple… but why won’t that work?

Answer 1

You can’t assign arrays like that, e.g.

char foo[500];
foo = "this won't work";

You have to use a function like strcpy

strcpy(new_disk.current_file[0].name, "new name");

strncpy would be safer, and std::string would be even safer.