---
name: "devname"
section: "3"
platform: "freebsd"
package: "base"
version: "16.0-CURRENT-20261027-61c70dc16a79"
release: "FreeBSD 16.0-CURRENT (2026-10-27)"
platforms: ["freebsd", "macos"]
url: "https://new.carta.tech/devname"
---

# devname(3)

get device name

## NAME

**devname** – get device name

## LIBRARY

Standard C Library (libc, -lc)

## SYNOPSIS

**#include \<sys/stat.h\>**

**#include \<stdlib.h\>**

*char* *\**\

**devname**(*dev\_t dev*, *mode\_t type*);

*char* *\**\

**devname\_r**(*dev\_t dev*, *mode\_t type*, *char \*buf*, *int len*);

*char* *\**\

**fdevname**(*int fd*);

*char* *\**\

**fdevname\_r**(*int fd*, *char \*buf*, *int len*);

## DESCRIPTION

The **devname**() function returns a pointer to the name of the block or character device in */dev* with a device number of *dev*, and a file type matching the one encoded in *type* which must be one of S\_IFBLK or S\_IFCHR. To find the right name, **devname**() asks the kernel via the *kern.devname* sysctl. If it is unable to come up with a suitable name, it will format the information encapsulated in *dev* and *type* in a human-readable format.

The **fdevname**() and **fdevname\_r**() function obtains the device name directly from a file descriptor pointing to a character device. If it is unable to come up with a suitable name, these functions will return a NULL pointer.

**devname**() and **fdevname**() return the name stored in a static buffer which will be overwritten on subsequent calls. **devname\_r**() and **fdevname\_r**() take a buffer and length as argument to avoid this problem.

## EXAMPLES

```
int fd;
struct stat buf;
char *name;
	fd = open("/dev/tun");
	fstat(fd, &buf);
	printf("devname is /dev/%s\n", devname(buf.st_rdev, S_IFCHR));
	printf("fdevname is /dev/%s\n", fdevname(fd));
```

## SEE ALSO

[stat(2)](/stat/2.md)

## HISTORY

The **devname**() function appeared in 4.4BSD. The **fdevname**() function appeared in FreeBSD 8.0.