Trouble with argv[]

[Seron]

Hello,

How could I compare command-line arguments to strings? I've got the code below that works with single characters. What should I change to make it work with strings?

int main(const int argc, char* argv[]) {

  bool v = false;
  for(int i = 1; i < argc; i++) {
    if(*argv[i] == 'v')
      v = true;
  }

Seron

[Stoned_Coder]

use strcmp() for null terminated c style strings.
for stl strings use member function compare()

[Seron]

I'm a beginner at C++ and have not come across strcmp() or compare() . Are there any resources on the web to learn more about how these are used?

Seron

[zMan]

strcmp, strcpy, strcat, and many others are part of the c library <string.h>


If you have any book on C++ or C it should talk about the use of these functions other wise this is how they work...


strcompare( string1, string2) will return 0 if they are equal < 0 if string1 is less than string 2 or > 0 if string2 is greater than string1.

e.g.

char string1[20] = "Mickey";
char string2[20] = "Pluto";

if( strcmp(string1, string2) == 0) result is false
if( strcmp(string1, string2) > 0) result is false
if( strcmp(string1, string2) < 0) result is true because Mickey < Pluto

In the case with the argv statements you would compare like this

if( strcmp(argv[1], "something") == 0)
..do something
else if( strcno( argv[2], "something") == 0)
...do something else
...

[Seron]

Thank you zMan.

One more question. Why is Mickey < Pluto ?

Seron