C-功能可以释放一系列字符串



背景故事:

我创建了一个函数,以破坏c。

中的一系列字符串

我将指针传递到该数组中的指针进入此功能,首先释放单个字符串,然后释放数组本身。

运行程序时,我会收到以下错误:

tokenDemo(4967,0x11afeb5c0) malloc: *** error for object 0x7fde73c02a05:pointer being freed was not allocated
tokenDemo(4967,0x11afeb5c0) malloc: *** set a breakpoint in malloc_error_break to debug
Abort trap: 6

我几乎可以肯定我会通过正确的指针。我想念什么?

代码:

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "token.h"
#define MAXLEN 100
int main(){
  //delimiters used for tokenization
  char sep[4] = {',',' ','n'};
  char *strin = (char*)malloc(MAXLEN * sizeof(char));
  printf("enter sentence: n");
  fgets(strin, (MAXLEN + 1), stdin);
  char** tokens = stringToTokens(strin, sep);
  int i=0;
  while(tokens[i] != NULL){
    reverse(tokens[i]);
    printf("%s ",tokens[i]);
    i++;
  }
  printf("n");
  printf("tokens: %dn*tokens: %sn", tokens, *tokens);
  destroyTokens(tokens);
  free(strin);
}


#define MAX 100 //this is the maximim number of words that can be tokenized
char **stringToTokens(char *str, char *sep){
  //malloc space for the array of pointers
  char **tokenArray = (char **) malloc(MAX * sizeof(char*));
  char * token = strtok(str, sep);
  int count = 0;
  while(token!=NULL){
    tokenArray[count] = token;
    count ++; //tracks number of words
    token = strtok(NULL, sep); //gets the next token in the string and sets it to token
  }
  tokenArray[count]=NULL; //adds null to last element
  return tokenArray;
}
void destroyTokens(char **tokenArray){
  //free the individual strings
  int i=0;
  while(tokenArray[i] != NULL){ 
        free(tokenArray[i]);
        i++;
    }
    free(tokenArray);
}
void reverse(char *s){
  int length = strlen(s);
  char *start, *end, temp;
  start=s;
  end=s;
  //now actually move end to the end of the string
  for(int i=0; i<length-1; i++){
    end++;
  }
  for(int i=0; i<length/2; i++){
    temp   = *end;
    *end   = *start;
    *start = temp;
    start++;
    end--;
  }
}

预先感谢!

strtok函数不会分配内存。它将指针返回到Char中的Char。因此,您不应为此发布内存。代码的这一部分:

while(tokenArray[i] != NULL){ 
    free(tokenArray[i]);
    i++;
}

必须省略

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