XvQueryPortAttributes(3) libXv Functions XvQueryPortAttributes(3)

# [NAME](#NAME)

XvQueryPortAttributes - return list of attributes of a video port

# [SYNOPSIS](#SYNOPSIS)

**#include <X11/extensions/Xvlib.h>**

```
XvAttribute* XvQueryPortAttributes(Display *dpy,
                 XvPortID port,  int *p_num_attributes);
```

# [ARGUMENTS](#ARGUMENTS)

[*dpy*](#dpy)

Specifies the connection to the X server.

[*port*](#port)

Specifies the port whose adaptor is to be queried for its list of attributes.

[*p\_num\_attributes*](#p_num_attributes)

A pointer to where the number of attributes returned in the array is written.

# [DESCRIPTION](#DESCRIPTION)

[**XvQueryPortAttributes**(3)](/man/os/libxv/XvQueryPortAttributes.3)**returns**the**number**of**attributes** and an array of XvAttributes valid for the given port. The array may be freed with [**XFree**(3)](/man/os/libxv/XFree.3).

# [RETURN VALUES](#RETURN_VALUES)

XvAttribute has the following structure:

```


    typedef struct {


      int flags;


      int min_value;


      int max_value;


      char *name;


    } XvAttribute;
```

[*flags*](#flags)

May be XvGettable or XvSettable or both OR'd together indicating the particular attribute is readable, writeable or readable and writeable.

[*min\_value*](#min_value)

The minimum attribute values which are valid for the driver.

The maximum attribute values which are valid for the driver.

[*name*](#name)

A string describing the name of the attribute that may be used to retrieve the Atom for the particular attribute.

# [DIAGNOSTICS](#DIAGNOSTICS)

\[XvBadPort]

Generated if the requested port does not exist.

# [SEE ALSO](#SEE_ALSO)

[**XvGetPortAttribute**(3)](/man/os/libxv/XvGetPortAttribute.3), [**XvSetPortAttribute**(3)](/man/os/libxv/XvSetPortAttribute.3)

libXv 1.0.13 X Version 11

---

Document: XvQueryPortAttributes(3) from libxv 1.0.13-r7 (Chainguard OS)
Source: https://gitlab.freedesktop.org/xorg/lib/libxv