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# mach_msg_header_t

```
typedef struct { ... } mach_msg_header_t;
```

## Topics

### Getting the Header Fields

[`mach_msg_bits_t msgh_bits;`](/documentation/DriverKit/mach_msg_header_t/msgh_bits)

[`mach_msg_id_t msgh_id;`](/documentation/DriverKit/mach_msg_header_t/msgh_id)

[`mach_port_t msgh_local_port;`](/documentation/DriverKit/mach_msg_header_t/msgh_local_port)

[`mach_port_t msgh_remote_port;`](/documentation/DriverKit/mach_msg_header_t/msgh_remote_port)

[`mach_msg_size_t msgh_size;`](/documentation/DriverKit/mach_msg_header_t/msgh_size)

[`mach_port_name_t msgh_voucher_port;`](/documentation/DriverKit/mach_msg_header_t/msgh_voucher_port)


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