---
name: "ares_parse_mx_reply"
section: "3"
platform: "linux"
package: "c-ares"
version: "1.34.9-1"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/ares_parse_mx_reply"
---

# ares\_parse\_mx\_reply(3)

Parse a reply to a DNS query of type MX

## NAME

ares\_parse\_mx\_reply - Parse a reply to a DNS query of type MX

## SYNOPSIS

\#include \<ares.h\>

int ares\_parse\_mx\_reply(const unsigned char\* *abuf*, int *alen*,\
                         struct ares\_mx\_reply\*\* *mx\_out*);

## DESCRIPTION

The **ares\_parse\_mx\_reply** function parses the response to a query of type MX into a linked list of *struct ares\_mx\_reply* The parameters *abuf* and *alen* give the contents of the response.  The result is stored in allocated memory and a pointer to it stored into the variable pointed to by *mx\_out*. It is the caller's responsibility to free the resulting *mx\_out* structure when it is no longer needed using the function **[ares\_free\_data(3)](/ares_free_data/3.md)**.

The structure  *ares\_mx\_reply* contains the following fields:

```
struct ares_mx_reply {
    struct ares_mx_reply *next;
    char *host;
    unsigned short priority;
};
```

## RETURN VALUES

**ares\_parse\_mx\_reply** can return any of the following values:

- **ARES\_SUCCESS**

  The response was successfully parsed.

- **ARES\_EBADRESP**

  The response was malformatted.

- **ARES\_ENODATA**

  The response did not contain an answer to the query.

- **ARES\_ENOMEM**

  Memory was exhausted.

## AVAILABILITY

This function was first introduced in c-ares version 1.7.2.

## SEE ALSO

[**ares\_query**(3)](/ares_query/3.md) [**ares\_free\_data**(3)](/ares_free_data/3.md)