argc/v question?

This is a discussion on argc/v question? within the Windows Programming forums, part of the Platform Specific Boards category; here is my partial code: Code: int main(int argc, char *argv[]) { // make sure that there is at least ...

  1. #1
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    argc/v question?

    here is my partial code:

    Code:
    int main(int argc, char *argv[])
    {
    
    	// make sure that there is at least 1 argument
    	if (argc < 2) {
    		usage();
    	}
    
    	switch (*argc[0]) 
    	{
    		case "-i":
    			myFunction(argc[0]);
    i get many errors. i am trying to input the arguments as strings, and use the arguments in myFunction that i am calling within the switch, any helpful hints?

  2. #2
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    i get many errors
    Maybe you should tell us what they are.

    I can tell you that one error definitely comes from
    Code:
    case "-i":
    You can't use string literals in case statements. To compare strings, you have to use the strcmp() function.

  3. #3
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    Oh, and
    Code:
    switch (*argc[0])
    is very wrong. Look at what variable you are using here.

  4. #4
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    Code:
    int main(int argc, char *argv[])
    {
    	// make sure that there is at least 1 argument
    	if (argc < 2) {
    		usage();
    	}
    	if (*argv[0] == "-i") {
    		i();
    	}
    	else if (*argv[0] == "-h") {
    	        h(*argv[2]);
    	}
    	else if (*argv[0] == "-r") {
    		r();
    	}
    	else {
    		usage();
    	}
    
    	return 0;
    }
    here are my warnings (were errors, switched to if, versus switch:

    test.c(7) : warning C4047: '==' : 'int ' differs in levels of indirection from 'char [3]'
    test.c(10) : warning C4047: '==' : 'int ' differs in levels of indirection from 'char [3]'
    test.c(11) : warning C4047: 'function' : 'char *' differs in levels of indirection from 'char '
    test.c(11) : warning C4024: 'portScan' : different types for formal and actual parameter 1
    test.c(13) : warning C4047: '==' : 'int ' differs in levels of indirection from 'char [3]'

  5. #5
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    I think this is what you are trying to do:
    Code:
    int main(int argc, char *argv[])
    {
    	// make sure that there is at least 1 argument
    	if (argc < 2) {
    		usage();
    		return 0;  // quit the program
    	}
    	if (!strcmp(argv[1],"-i")) { // Check if the first argument is equal to -i
    		i();
    	}
    	else if (!strcmp(argv[1],"-h")) {
    	        h(argv[2]);
    	}
    	else if (!strcmp(argv[1],"-r"))  {
    		r();
    	}
    	else {
    		usage();
    		return 0;
    	}
    
    	return 0;
    }
    Note that you are misunderstanding the arguments. Let's say your program was run like the fillowing:
    myprogram.exe -h hello

    Now here is what your arguments look like:
    argv[0] = "myprogram.exe"
    argv[1] = "-h"
    argv[2] = "hello"

    In order to see if a string is equal to something, you cannot use ==, you need to use strcmp() like in my example.

  6. #6
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    And what happens when I do this:
    myprogram.exe -i -h hello -r

    Doesn't windows have an equivalent of getoptlong?

  7. #7
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    Doesn't windows have an equivalent of getoptlong?
    Nothing standard, but there are people out there that have programmed the equivalent. codeproject has a couple examples.

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