Description abraham 2010-10-27 15:52:37 EDT

Build Identifier: M20090917-0800

In C the life span of a variable in a function should only last till the end of the function but that is not happening in eclipse CDT. For example if I have a value returning function like this one: newString = stringToUpCase(usrString);
stringToUpCase returns a pointer to char then if you haven't allocated memory to keep the contents of the pointer to char then it is suppose to return garbage but that is not happening. Here's an example with my code:

#include <stdio.h>
#include <string.h>
#include <stddef.h>

#define STRING_LENGTH 71

void getString(char *);
char *stringToUpCase(char *);

int main(void) {
	char usrString[STRING_LENGTH];
	char * newString;
	
	getString(usrString);

	newString = stringToUpCase(usrString);

	printf("This is the Upper-Case string: %s\n", newString);

	getchar();
	return 0;
}

void getString(char * usrString) {
	char tempString[STRING_LENGTH];

	printf("Enter any type of string: ");

	fflush(stdout);
	gets(tempString);

	strcpy(usrString, tempString);
}
char *stringToUpCase(char * aString) {
	int i , strLen = strlen(aString);

	char charArray[STRING_LENGTH];

	for(i = 0; i < strLen; i++) {
		if(*(aString +i) >= 'a' && *(aString +i) <= 'z')
				charArray[i] = (*(aString + i)) - 32;

	}
	charArray[strLen] = '\0';

	return charArray;
} 

here is picture of what I mean: http://i553.photobucket.com/albums/jj362/cabbae/error.jpg

now the correct way to keep the contents of charArray is to allocate memory. Heres an example:
char *stringToUpCase(char * aString) {
	int i , strLen = strlen(aString);

	char *charPtr = NULL;
	charPtr = malloc(strLen * sizeof(char));

	for(i = 0; i < strLen; i++) {
		if(*(aString +i) >= 'a' && *(aString +i) <= 'z')
				charPtr[i] = (*(aString + i)) - 32;

	}
	charPtr[strLen] = '\0';

	return charPtr;
}

Reproducible: Always