---
name: "nbd_is_uri"
section: "3"
platform: "linux"
package: "libnbd"
version: "1.24.4-1"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/nbd_is_uri"
---

# nbd\_is\_uri(3)

detect if a string could be an NBD URI

## NAME

nbd\_is\_uri - detect if a string could be an NBD URI

## SYNOPSIS

```
 #include <libnbd.h>
 int nbd_is_uri (
       struct nbd_handle *h, const char *uri
     );
```

## DESCRIPTION

Detect if the parameter `"uri"` could be an NBD URI or not. The function returns true if `"uri"` is likely to be an NBD URI, or false if not.

This can be used to write programs that take either a URI or something else like a filename as a parameter.  [**nbdcopy**(1)](/nbdcopy/1.md) is one such program.

The current test is heuristic.  In particular it *does not* guarantee that [**nbd\_connect\_uri**(3)](/nbd_connect_uri/3.md) will work.

## RETURN VALUE

This call returns a boolean value.

## ERRORS

On error `-1` is returned.

Refer to "ERROR HANDLING" in [**libnbd**(3)](/libnbd/3.md) for how to get further details of the error.

The following parameters must not be NULL: `"h"`, `"uri"`. For more information see "Non-NULL parameters" in [**libnbd**(3)](/libnbd/3.md).

## VERSION

This function first appeared in libnbd 1.22.

If you need to test if this function is available at compile time check if the following macro is defined:

```
 #define LIBNBD_HAVE_NBD_IS_URI 1
```

## SEE ALSO

[**nbd\_aio\_connect\_uri**(3)](/nbd_aio_connect_uri/3.md), [**nbd\_connect\_uri**(3)](/nbd_connect_uri/3.md), [**nbd\_create**(3)](/nbd_create/3.md), [**nbd\_get\_uri**(3)](/nbd_get_uri/3.md), [**nbd\_supports\_uri**(3)](/nbd_supports_uri/3.md), [**libnbd**(3)](/libnbd/3.md), [**nbdcopy**(1)](/nbdcopy/1.md).

## AUTHORS

Eric Blake

Richard W.M. Jones

## COPYRIGHT

Copyright Red Hat

## LICENSE

This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License along with this library; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA