c - 在C中释放内存的问题

Question

Closed. This question is off-topic。它当前不接受答案。
                            
                        
                    
                
                            
                                
                
                        
                            
                        
                    
                        
                            想改善这个问题吗？ Update the question，所以它是 on-topic，用于堆栈溢出。
                        
                        2年前关闭。
                                                                                            
                
        
我正在编写一个C程序，并分配了一些内存，当我尝试释放它时，出现了段错误。不知道我在做什么错。这是函数：
我仅在释放令牌而不是registro时收到错误。

void cargarArchivo(struct fila *arregloArchivo){
    FILE *csv = fopen("datos_meteorologicos.CSV","r");              
    char *registro;
    char *token;        
    struct fila local;      
    int i;  
    int j;

    registro = (char *)malloc(sizeof(char));    
    token = (char *)malloc(100*sizeof(char));

    size_t characters;
    size_t registro_size = 32;

    if(registro==NULL || arregloArchivo==NULL){
        printf("%s\n", "Problemas alocando memoria, no hay suficiente");
        exit(1);
    }   
    while(-1 != getline(&registro,&registro_size,csv)){
        token = strtok(registro,",");
        for(j=0;j<cantDatos+1;j++){   
            if(j<1){
                token = strtok(NULL,",");
                token = strtok(NULL,",");
                token = strtok(NULL,",");
                token = strtok(NULL,",");
                token = strtok(NULL,",");
                token = strtok(NULL,",");
                token = strtok(NULL,",");
                token = strtok(NULL,",");
                token = strtok(NULL,",");
                token = strtok(NULL,",");
                token = strtok(NULL,",");
                token = strtok(NULL,",");
                token = strtok(NULL,",");
                token = strtok(NULL,",");
                token = strtok(NULL,",");
                token = strtok(NULL,",");
                token = strtok(NULL,",");
                token = strtok(NULL,",");
                token = strtok(NULL,",");
                token = strtok(NULL,",");
            }

            else if(j==1){

                local.numero = atoi(token);

    //printf("numero:%d\n",local.numero );
                token = strtok(NULL,",");    
                strcpy(local.estacion,token);

    //printf("estacion:%s\n",local.estacion );    
                token = strtok(NULL,",");    
                local.localidad = atoi(token);

    //printf("loca%d\n",local.localidad );
                token = strtok(NULL,",");    
                strcpy(local.fecha,token);

    //printf("fec%s\n",local.fecha );
                    token = strtok(NULL,",");    
                local.temperatura = atof(token);

    //printf("temperatura%f\n",local.temperatura );    
                token = strtok(NULL,",");    
                local.porcentajeHumedad = atof(token);

    //printf("porHum: %f\n",local.porcentajeHumedad );    
                token = strtok(NULL,",");    
                local.puntoRocio = atof(token);

    //printf("punto rocio: %f\n",local.puntoRocio );    
                token = strtok(NULL,",");    
                local.precipitacion = atof(token);

    //printf("prec:%f\n",local.precipitacion );    
                token = strtok(NULL,",");    
                local.velocidadViento = atof(token);


    //printf("velviento:%f\n",local.velocidadViento );    
                token = strtok(NULL,",");    
                strcpy(local.dirViento,token);

    //printf("dirviento: %s\n",local.dirViento );    
                token = strtok(NULL,",");
                local.rafagaMax = atof(token);

    //printf("rafagamax: %f\n",local.rafagaMax );    
                token = strtok(NULL,",");    
                local.presion = atof(token);

    //printf("presion:%f\n",local.presion );    
                token = strtok(NULL,",");    
                local.radiacionSolar = atof(token);

    //printf("rad:%f\n",local.radiacionSolar );    
                token = strtok(NULL,",");    
                local.tempSuelo1 = atof(token);

    //printf("tempSuelo1:%f\n",local.tempSuelo1 );
                token = strtok(NULL,",");    
                local.tempSuelo2 = atof(token);

    //printf("tempSuelo2:%f\n",local.tempSuelo2 );    
                token = strtok(NULL,",");    
                local.tempSuelo3 = atof(token);

    //printf("tempSuelo3:%f\n",local.tempSuelo3 );    
                token = strtok(NULL,",");    
                local.humedadSuelo1 = atof(token);

    //printf("humedad1: %f\n",local.humedadSuelo1 );    
                token = strtok(NULL,",");    
                local.humedadSuelo2 = atof(token);

    //printf("humedad2: %f\n",local.humedadSuelo2 );    
                token = strtok(NULL,",");    
                local.humedadSuelo3 = atof(token);

    //printf("humedad3: %f\n",local.humedadSuelo3 );    
                token = strtok(NULL,", ");    
                local.humedadHoja = atof(token);

    //printf("hum hoja: %f\n",local.humedadHoja );

                arregloArchivo[j-1] = local;    
            }else{    
                token = strtok(NULL,",");        
                local.numero = atoi(token);

    //printf("num: %d\n",local.numero);    
                token = strtok(NULL,",");    
                strcpy(local.estacion,token);

    //printf("estacion:%s\n",local.estacion );    
                token = strtok(NULL,",");    
                local.localidad = atoi(token);

    //printf("loca%d\n",local.localidad );    
                token = strtok(NULL,",");    
                strcpy(local.fecha,token);

    //printf("fec%s\n",local.fecha );    
                token = strtok(NULL,",");    
                local.temperatura = atof(token);

    //printf("temperatura%f\n",local.temperatura );    
                token = strtok(NULL,",");    
                local.porcentajeHumedad = atof(token);

    //printf("porHum: %f\n",local.porcentajeHumedad );    
                token = strtok(NULL,",");    
                local.puntoRocio = atof(token);

    //printf("punto rocio: %f\n",local.puntoRocio );    
                token = strtok(NULL,",");    
                local.precipitacion = atof(token);

    //printf("prec:%f\n",local.precipitacion );    
                token = strtok(NULL,",");
                local.velocidadViento = atof(token);

    //printf("velviento:%f\n",local.velocidadViento );    
                token = strtok(NULL,",");    
                strcpy(local.dirViento,token);

    //printf("dirviento: %s\n",local.dirViento );    
                token = strtok(NULL,",");    
                local.rafagaMax = atof(token);

    //printf("rafagamax: %f\n",local.rafagaMax );    
                token = strtok(NULL,",");
                local.presion = atof(token);

    //printf("presion:%f\n",local.presion );    
                token = strtok(NULL,",");
                local.radiacionSolar = atof(token);

    //printf("rad:%f\n",local.radiacionSolar );    
                token = strtok(NULL,",");    
                local.tempSuelo1 = atof(token);

    //printf("tempSuelo1:%f\n",local.tempSuelo1 );    
                token = strtok(NULL,",");    
                local.tempSuelo2 = atof(token);

    //printf("tempSuelo2:%f\n",local.tempSuelo2 );    
                token = strtok(NULL,",");    
                local.tempSuelo3 = atof(token);

    //printf("tempSuelo3:%f\n",local.tempSuelo3 );
                token = strtok(NULL,",");    
                local.humedadSuelo1 = atof(token);

    //printf("humedad1: %f\n",local.humedadSuelo1 );    
                token = strtok(NULL,",");    
                local.humedadSuelo2 = atof(token);

    //printf("humedad2: %f\n",local.humedadSuelo2 );    
                token = strtok(NULL,",");    
                local.humedadSuelo3 = atof(token);

    //printf("humedad3: %f\n",local.humedadSuelo3 );    
                token = strtok(NULL,", ");
                    local.humedadHoja = atof(token);

    //printf("hum hoja: %f\n",local.humedadHoja );
                arregloArchivo[j-1] = local;    
            }   
        }        
    }

    free(registro);

    printf("%s\n","Fin de la carga." );

    free(token);
    printf("%s\n","libere token" );
    fclose(csv);

}

最佳答案

@Daan Gerlack的注释中的答案正确的原因是，您正在通过将token的返回值分配给它来更改strtok()的值。

因此，要解决此问题，您可以在字符串的开头存储一个引用（也称为指针），这是唯一的指针值free()将接受以指示您分配的内存块，并使用该引用释放内存。

关于c - 在C中释放内存的问题，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/46203870/

上一篇：c - NULL是如何终止的？

下一篇：c - 如何使用 C 语言的套接字将客户端连接到 IRC 服务器

相关文章：

memory - 运行时，唯一存储在 tmpfs 中的可执行代码是否会复制到 RAM 的另一部分？

python - 为什么作为列表的文本表示会消耗如此多的内存？

c - 段错误(核心转储)

c - 使用 scanf 在 C 中读取多个值

linux - 在 Linux 2.6.x 下访问任何内存位置

C:将结构读入链接列表(从文件)

c - 使用 memcpy 时出现段错误

c - 最小化 malloc() 调用量可以提高性能？

c - "Bad permissions for mapped region at address"哈希表的 Valgrind 错误

ios - 未声明的类型 - 通过桥接 header 在 Swift 中使用 C 结构

Answer 1

@Daan Gerlack的注释中的答案正确的原因是，您正在通过将token的返回值分配给它来更改strtok()的值。

因此，要解决此问题，您可以在字符串的开头存储一个引用（也称为指针），这是唯一的指针值free()将接受以指示您分配的内存块，并使用该引用释放内存。