How to convert properly char * const[256] to const char * const*

Question

I have this struct:

typedef struct cmdLine {
char * const arguments[256];
} cmdLine;

I also have an argument cmdLine *pCmdLine. I want to use execvso I write execv((pCmdLine->arguments[0]), pCmdLine->arguments);. The second argument doesn't feet properly to execvand I want to ask how to convert it properly.

The warning I get is: Passing 'char* const[256]'' to parameter of type 'const char *const *' discards qualifiers in nested pointer types. I would lie for some help to convert it properly, thanks.

Please post a [Minimal, Complete, and Verifiable example](https://stackoverflow.com/help/mcve). — H.S., Apr 20 '19 at 11:04
Why can't you make it the appropriate type (`char const * const[256]`) to begin with? — molbdnilo, Apr 20 '19 at 11:25
Because `cmdLine` is a struct I got as a requirement to the project. — J. Doe, Apr 20 '19 at 13:17
Interesting... the POSIX headers list the prototype for `execv` as *`int execv(const char *path, char *const argv[]);`* - what system are you targetting? — Antti Haapala -- Слава Україні, Apr 20 '19 at 13:58
There is no `execve` in Windows 10, there is `_execve` which has `const char * const` suitable for C++ — Antti Haapala -- Слава Україні, Apr 20 '19 at 14:27
I'm sorry, I'm not very familiar with the expresions so I didn't understand what you were asking. — J. Doe, Apr 20 '19 at 14:29

score 0 · Answer 1 · answered Apr 20 '19 at 11:18

I do not see any problems:

#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>

#include <stdio.h>

struct
{
char * const arr[20];
}*str;

void foo(char  *const par[])
{
    volatile const char * const ptr = par[4]; 
    printf("%s\n", par[7]);
    printf("%s\n", ptr);
}


void foo1()
{
    foo(str -> arr);
}

https://godbolt.org/z/4Sv4a8

How to convert properly char * const[256] to const char * const*

1 Answers1