C - Error with function parameters when it is being called - c

Question

When I am trying to call a function, the parameters that I have tried so far have just resulted in the terminal saying that 'too few arguments to function' and what I can tell that what it wants written there is the parameters from when it was declared. I have read a few different documents about this and what the calling parameters are and the different between calling by value or by reference but I am still not able to figure out the problem.
Below is the main section of code that has the call functions in it along with some variables.
int main(int argc, char *argv[])
{//main()
char *listwords;
processfile(listwords); //<- this is the line that is causing the problem
WordList mylist;
initialiselist(&mylist);
addword(&mylist, createfillednode(listwords));
printlist(&mylist);
}//main()
Below here is the processfile() function:
//process the file
void processfile(WordList *wordList, int argc, char *argv[])
{//process file
//file pointer
FILE *f;
//open the file
f = fopen(argv[1], "r");
//check it opened correctly
if(f == NULL)
{//if statement
printf("cannot read file\n");
}//if statement
fseek(f, 0, SEEK_END);
//declare variables
char *listwords;
long size = ftell(f);
char *token;
//seek beginning of file
fseek(f, 0, SEEK_SET);
//set the size of array to the file size
listwords = (char*)malloc(size+1);
listwords[size] = '\0';
//reads the data from the file
fread(listwords, size, 1, f);
int i;
for(i=0; (token = strsep(&listwords, " ")); i++)
{//for loop replace certain characters with spaces
if (token != ".")
{
//pointer from the token to the dictionary
wordList->token;
}else if (wordList->token != "!")
{
wordList->token;
}else if (token != "?")
{
wordList->token;
}else if (token != "\"")
{
wordList->token;
}else if (token != ","){
wordList->token;
}else
{
wordList->token;
}
//increment token to the next word
token++;
}//for loop replace certain characters with spaces
fclose(f);
return;
}//process file
Thanks.

Answer 1

You've declared processfile to take three arguments.
void processfile(WordList *wordList, int argc, char *argv[])
But you're only giving it one.
processfile(listwords);
And it's also the wrong type. It should be a WordList, but instead it's a string (char *).
char *listwords;
In C, you have to give a function exactly the right number of arguments and of the right type (C can do some type casting, but it's strictly defined and usually about numbers).
With one exception. Variadic arguments let you pass an undefined number of arguments. This is how functions like printf work. In general you should avoid variadic functions as much as possible, they add complexity and defeat type checking.
In your case, processfile only needs two arguments: a list of words, and a filename to open. argc is never used, and knowing that the filename is coming from argv[1] puts an unnecessary restriction on the function.
void processfile(WordList *wordList, char *filename)
Then it can be called with...
WordList *wordList = ...generate the wordlist somehow...
processfile(wordList, argv[1]);

Answer 2

The processfile() function takes three arguments according to your definition:
void processfile(WordList *wordList, int argc, char *argv[])
However, in your main() function you're only passing a single argument:
processfile(listwords)
To make this work like you'd want it to, you'd have to pass all three arguments; your listwords, as well as the counter and vector for arguments:
processfile(listwords, argc, argv)
However, in general, this is usually not a great idea programatically speaking as far as I know. A function should typically take some sort of specialized input and return a relevant value, and not the input from the command line - that should be parsed far ahead of the function actually being called. Check out getopt or argparse to process arguments correctly, determine what parameters you really want to pass to processfile() and pass only the arguments that would be relevant to the file in which you're attempting to process. From reading your code, probably just the file descriptor, which should be opened in main() after some argument-parsing error correction:
void processfile(WordList *wordList, FILE *f)
{
fseek(f, 0, SEEK_END);
//declare variables
char *listwords;
long size = ftell(f);
char *token;
fseek(f, 0, SEEK_SET);
listwords = (char*)malloc(size+1);
listwords[size] = '\0';
fread(listwords, size, 1, f);
- - - - - - - - - 8< - - - - - - - - -
This way, you can open your file elsewhere, and re-use processfile() on any open file called in any context, making it a more robust function.