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POmemory leak for simple program, how can I free allocs?
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15169946
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2013-03-02T02:15:50.497
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2013-03-02T04:15:14.853
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I am learning C, and am have a problem finding out how i can free my malloc()'s. The program runs correctly.. but im Using valgrind and it is coming up with 8 allocs and 5 frees. I need to be able to free 3 more. I commented where I believe which I am not freeing but I am not sure of a solution. Is there a way I can free up those allocs, or do I need to consider re-writing the tokenizer()? Here is the code to the whole file. <pre><code>#include <stdlib.h> #include <stdio.h> #include <string.h> char *substr(const char *s, int from, int nchars) { char *result = (char *) malloc((nchars * sizeof(char))+1); strncpy(result, s+from, nchars); return result; } /** Extracts white-space separated tokens from s. @param s A string containing 0 or more tokens. @param ntokens The number of tokens found in s. @return A pointer to a list of tokens. The list and tokens must be freed by the caller. */ char **tokenize(const char *s, int *ntokens) { int fromIndex = 0; int toIndex = 0; char **list; int finalCount = *ntokens; int count = 0; list = malloc(*ntokens * sizeof(char*)); while ( count < finalCount) { char *m = strchr(s,' '); toIndex = m - s; if(toIndex >= 0) { list[count] = substr(s,fromIndex,toIndex); // This substr() gets free'ed from main() s = substr(s, toIndex+1, strlen(s)); // I believe This is where I am making extra mallocs that are not being freed count++; } else { list[count] = substr(s,fromIndex,strlen(s)); // This substr() gets free'ed from main() count++; } } return list; } int main(int argc, char **argv) { char **list; char *string = "terrific radiant humble pig"; int count = 4; // Hard-Coded list = tokenize(string, &count); for (int i=0;i<count;i++) { printf("list[%d] = %s\n", i, list[i]); } // Free mallocs()'s for (int i=0;i<count;i++) { free(list[i]); } // Free List free(list); return 0; } </code></pre>
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memory leak for simple program, how can I free allocs?
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