convert const char* to NSString * and convert back - _NSAutoreleaseNoPool()

Question

i'm trying to convert const char* to NSString * and then convert it back. It works, but i get:

__NSAutoreleaseNoPool(): Object 0x100550a40 of class NSCFArray autoreleased with no pool in place - just leaking
__NSAutoreleaseNoPool(): Object 0x100551730 of class NSCFString autoreleased with no pool in place - just leaking
__NSAutoreleaseNoPool(): Object 0x100551f10 of class NSCFData autoreleased with no pool in place - just leaking

The code is:

const char* convert = "hello remove this: *";

NSString *input = [[NSString alloc] initWithUTF8String:convert];// convert 

//remove * FROM THE STRING          
NSCharacterSet *doNotWant = [NSCharacterSet characterSetWithCharactersInString:@"*"]; 

// REPLACE * WITH NOTHING                   
input = [[input componentsSeparatedByCharactersInSet: doNotWant] componentsJoinedByString: @""];

// CONVERT BACK         
const char *converted_back = [input UTF8String]; 

I'm lost, please help me out.

Answer 1

If you are doing it in a background thread, add an NSAutoReleasePool.

NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init];
const char* convert = "hello remove this: *";
NSString *input = [[[NSString alloc] initWithUTF8String:convert] autorelease];// convert 
//remove * FROM THE STRING          
NSCharacterSet *doNotWant = [NSCharacterSet characterSetWithCharactersInString:@"*"]; 
// REPLACE * WITH NOTHING                   
input = [[input componentsSeparatedByCharactersInSet: doNotWant] componentsJoinedByString: @""];
// CONVERT BACK         
const char *converted_back = [input UTF8String]; 
[pool drain];

Also, you need to release input after you're done with it, or make it autoreleased.