Programming Forums > Application Development > C

atreyu · Jul 22nd, 2005, 10:42 AM

perlwhore new to C...

My 'C for Linux Programming' book says that 'char' is a valid return type for functions, but I can't get my function to return a non-int value. I searched the boards, and googled, but i can find no example. If return can't return a non-int, what's the point of using char as the function return type?

I get the following error:

In function `my_func':
warning: return makes integer from pointer without a cast

here's my code:

(Toggle Plain Text)

#include <stdio.h>
char my_func(char s[]);

int main(){
  char func_said;
  char string[] = "foo";
  func_said = my_func(string);
  return 0;
}

char my_func(char s[]) {
  return s;
}

sorry if i'm lame. tia.

stevengs · Jul 22nd, 2005, 11:14 AM

Quote:

Originally Posted by atreyu

here's my code:

(Toggle Plain Text)

#include <stdio.h>
char my_func(char s[]);

int main(){
  char func_said;
  char string[] = "foo";
  func_said = my_func(string);
  return 0;
}

char my_func(char s[]) {
  return s;
}

sorry if i'm lame. tia.

well, your function wants to return a single char, but you are telling it to return s, which is char []. There is a big difference between the two. What
you are probably wanting is something along the lines of:
return s[0];
To return the first char in "foo".

example:

(Toggle Plain Text)

#include <stdio.h>
char my_func1(char s[]);
char* my_func2(char s[]);

int main(){

	char* func_says;
	char func_said;
	char string[] = "foo";
	func_said = my_func1(string);
	func_says = my_func2(string);
	return 0;
}

char my_func1(char s[]) {
  return s[0];
}

char* my_func2(char s[]) {
  return s;
}

You can basically return any little thing you fancy, as long as you declare it properly, and dont' lose it due to it being local (which is allowed, but will usually end in an exception).

DaWei · Jul 22nd, 2005, 11:20 AM

Actually, you're telling it to return a char *, which isn't the same thing as an array of char, which might be assumed from your notation (Stevens didn't make that assumption, just mentioning it). The compiler often treats them in the same way, but there be vinegar in that wine bottle. See the section, CONFUSTOIDS, in the pointers material referenced in my signature.

stevengs · Jul 22nd, 2005, 11:31 AM

yeah, between char[], char*, char* [], char **, std::string, etc, I get pretty darned confusticated myself! (prolly shows)

skuinders · Jul 22nd, 2005, 11:43 AM

Quote:

Originally Posted by atreyu

perlwhore...

lol wtf?? Sorry, I stopped reading right there.

DaWei · Jul 22nd, 2005, 12:10 PM

I would presume that's someone who stands around on the beach (sans spell checker) in a slinky outfit, waiting for the boats to come back from the oyster beds

.

atreyu · Jul 22nd, 2005, 12:13 PM

stevengs,
danke! that damn asterisk...

DaWei,
i'm afraid you and stevengs way confusticated me with your C reparte, but thx 4 chiming in.

skuinders,
seesnob.

Jul 22nd, 2005, 10:42 AM	#1
atreyu Newbie Join Date: Jul 2005 Posts: 2 Rep Power: 0	using `char' return type in functions perlwhore new to C... My 'C for Linux Programming' book says that 'char' is a valid return type for functions, but I can't get my function to return a non-int value. I searched the boards, and googled, but i can find no example. If return can't return a non-int, what's the point of using char as the function return type? I get the following error: In function `my_func': warning: return makes integer from pointer without a cast here's my code: (Toggle Plain Text) #include <stdio.h> char my_func(char s[]); int main(){ char func_said; char string[] = "foo"; func_said = my_func(string); return 0; } char my_func(char s[]) { return s; } #include <stdio.h> char my_func(char s[]); int main(){ char func_said; char string[] = "foo"; func_said = my_func(string); return 0; } char my_func(char s[]) { return s; } sorry if i'm lame. tia.

Jul 22nd, 2005, 11:20 AM	#3
DaWei Resident Grouch Join Date: Jun 2005 Posts: 6,453 Rep Power: 10	Actually, you're telling it to return a char , which isn't the same thing as an array of char, which might be assumed from your notation (Stevens didn't make that assumption, just mentioning it). The compiler often treats them in the same way, but there be vinegar in that wine bottle. See the section, CONFUSTOIDS, in the pointers material referenced in my signature. __________________ Abstraction doesn't make it impossible to write bad code; it makes it possible to write superior code. Contributor's Corner: Grumpy on C++ Exceptions DaWei on Pointers*

Jul 22nd, 2005, 11:31 AM	#4
stevengs Professional Programmer Join Date: May 2005 Location: Bad Nauheim, Germany Posts: 436 Rep Power: 4	yeah, between char[], char, char [], char **, std::string, etc, I get pretty darned confusticated myself! (prolly shows) __________________ -Steven "Is this a piece of your brain?" - Basil Fawlty

Jul 22nd, 2005, 12:10 PM	#6
DaWei Resident Grouch Join Date: Jun 2005 Posts: 6,453 Rep Power: 10	I would presume that's someone who stands around on the beach (sans spell checker) in a slinky outfit, waiting for the boats to come back from the oyster beds . __________________ Abstraction doesn't make it impossible to write bad code; it makes it possible to write superior code. Contributor's Corner: Grumpy on C++ Exceptions DaWei on Pointers

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Jul 22nd, 2005, 12:13 PM	#7
atreyu Newbie Join Date: Jul 2005 Posts: 2 Rep Power: 0	stevengs, danke! that damn asterisk... DaWei, i'm afraid you and stevengs way confusticated me with your C reparte, but thx 4 chiming in. skuinders, seesnob.

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Programming Forums > Application Development > C

using `char' return type in functions