passing argument 2 of ‘write’ makes point er from integer without a cast [-Wint-conversion]

这个问题是在使用系统调用`write()`时，第二个参数的类型不正确导致的。`write()`函数的第二个参数应该是一个`const void*`类型，表示要写入的数据的地址。但是如果你传入的是一个整数类型（如`int`或`long`），编译器就会发出警告，提示你需要进行类型转换。

如果你想写入一个整数类型的数据，可以使用类型转换将其转换为指针类型，例如：

int data = 123;
write(fd, &data, sizeof(int));

在这个例子中，我们使用了`&`运算符获取了`data`变量的地址，并将其转换为`const void*`类型，然后传入`write()`函数中。注意，我们还需要传入要写入的数据的长度，这里使用了`sizeof(int)`来获取整数类型的长度。

相关问题

passing argument 1 of 'search' makes pointer from integer without a cast [-Wint-conversion]

This warning message typically occurs when you are passing an integer value to a function that expects a pointer as its argument. The compiler is warning you that there is a mismatch between the type of the argument you are passing and the type the function expects.

To fix this warning, you should ensure that you are passing the correct type of argument to the function. If the function expects a pointer, you should pass a pointer variable or address. If you are passing an integer value, you may need to cast it to a pointer type before passing it to the function.

For example, consider the following code:

int search(int *array, int size, int key) {
    // implementation of search function
}

int main() {
    int arr[] = {1, 2, 3, 4, 5};
    int key = 3;
    int index = search(key, arr, 5);
    // rest of the code
}

Here, we are passing the arguments to the `search` function in the wrong order. The function expects an array pointer as its first argument, but we are passing an integer value (`key`) instead. To fix this, we should swap the order of the arguments:

int main() {
    int arr[] = {1, 2, 3, 4, 5};
    int key = 3;
    int index = search(arr, 5, key);
    // rest of the code
}

If you are still getting the warning message after correcting the argument types, you may need to check the function declaration to ensure that it matches the expected argument types.

passing argument 1 of 'printf' makes pointer from integer without a cast [-Wint-conversion]

这个错误通常是因为在使用 `printf` 函数时，传递了一个整数而不是指针类型的参数。 `printf` 函数需要传递与格式化字符串中占位符对应的参数类型，例如 `%d` 对应整数类型，`%f` 对应浮点类型等等。如果传递了错误的参数类型，就会出现这个错误。

例如，以下代码会出现这个错误：

int age = 25;
printf("My age is %s", age);

正确的做法应该是将 `%s` 改成 `%d`，将整数类型的 `age` 传递给 `printf` 函数：

int age = 25;
printf("My age is %d", age);