Question

given the following code:

/* signatures */
int getParams(char params[MAX_PARAM_LEN][MAX_LINE_LEN]);
int getVersion(const char params[MAX_PARAM_LEN][MAX_LINE_LEN],
               const char* tagName );
/* initializing */
char params[MAX_PARAM_LEN][MAX_LINE_LEN] = {};

/* getting parameters */
paramCount = getParams(params); /* OK, params match with getParams signature */

/* processing the params array */
i = getVersion(params, "version"); /* warning: passing arg 1 of `getVersion' from incompatible pointer type */

I see that the constness is the problem, but I don’t know why or how to avoid it. What I want is a function which can’t modify the params anymore. Any advice is welcome(besides disabling this warning or deleting const in the processing function).

Thanks:
Visko

Answer 1

You can’t eliminate these warnings in C without making an explicit cast to the proper type. Without a typedef this is going to look ugly though

i = getVersion((const char (*)[MAX_LINE_LEN]) params, "version")

This is a strange quirk specific to C language. In C++ this issue was fixed.

BTW, the {} initializer is illegal in C. How did you manage to get that to compile?