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Hello again,
This time I am wondering whether creating a structure like: And then making a linked list with all my desired commands is not an overkill ? I would have then to create a for and compare every element of linked list with my command buffer string to execute some command.
On the other hand I am also thinking about simple if if if if...
Thanks for advices.

no need for struct, just a simple function that uses the function pointer, that's all

verynewbienoob wrote:

Code: Select all

struct commands
{
     char command = "example"
     (*func_ptr[option])();
}

Your struct looks a bit funny. Is that supposed to be "char *" instead of "char"? What kind of function pointer declaration is that?

verynewbienoob wrote:linked list

Will you be adding or removing commands at runtime? If yes, a binary search tree will have better performance while using a similar amount of memory. If no, a sorted array and a binary search will have better performance while using a similar amount of memory.

Octocontrabass wrote:

verynewbienoob wrote:

Code: Select all

struct commands
{
     char command = "example"
     (*func_ptr[option])();
}

Your struct looks a bit funny. Is that supposed to be "char *" instead of "char"? What kind of function pointer declaration is that?

verynewbienoob wrote:linked list

Will you be adding or removing commands at runtime? If yes, a binary search tree will have better performance while using a similar amount of memory. If no, a sorted array and a binary search will have better performance while using a similar amount of memory.

Yes, that is supposed to be pointer to char.

In my kernel debug shell I keep an array of names/commands/help text, and when the shell first starts I load it into a hash map so that commands can be looked up by name. This makes processing commands straightforward. The hashmap is overkill, but it allows for easy runtime addition of more commands.