Programming Forums > Application Development > C

titaniumdecoy · Apr 5th, 2008, 3:41 PM

I am confused as to the difference between a char array and a char pointer in C. For example:

char a[] = "one";
char *b = "two"

As I understand it, both are essentially pointers to the first character of an array except a can be modified and b cannot. Why is this?

If I then write char *c = a;, can c be used to modify the character array a?

Compare the following two functions declarations:

(Toggle Plain Text)

void f1(char x[]);
void f2(char *x);

If I pass a char[] to f2, can I modify it, or only if I pass it to f1? I assume it would be incorrect to pass a char* to f1--is this true?

Finally, compare the following two declarations for main:

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int main(int argc, char *argv[]);
int main(int argc, char **argv);

Does the latter indicate that the contents of argv can be modified? Or are the two declarations identical?

Thanks for any help clearing this up.

Apr 5th, 2008, 3:41 PM	#1
titaniumdecoy Expert Programmer Join Date: Nov 2005 Posts: 855 Rep Power: 3	char[] vs char* I am confused as to the difference between a char array and a char pointer in C. For example: (Toggle Plain Text) char a[] = "one"; char b = "two" char a[] = "one"; char b = "two" As I understand it, both are essentially pointers to the first character of an array except a can be modified and b cannot. Why is this? If I then write `char c = a;`, can c be used to modify the character array a? Compare the following two functions declarations: (Toggle Plain Text) void f1(char x[]); void f2(char x); void f1(char x[]); void f2(char x); If I pass a char[] to f2, can I modify it, or only if I pass it to f1? I assume it would be incorrect to pass a char to f1--is this true? Finally, compare the following two declarations for main: (Toggle Plain Text) int main(int argc, char argv[]); int main(int argc, char argv); int main(int argc, char argv[]); int main(int argc, char **argv); Does the latter indicate that the contents of argv can be modified? Or are the two declarations identical? Thanks for any help clearing this up.

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Programming Forums > Application Development > C

char[] vs char*