DEVNAME(3) BSD Library Functions Manual DEVNAME(3)NAME
devname — get device name
Standard C Library (libc, -lc)
devname(dev_t dev, mode_t type);
devname_r(dev_t dev, mode_t type, char *buf, int len);
fdevname_r(int fd, char *buf, int len);
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
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.
struct stat buf;
fd = open("/dev/tun");
printf("devname is /dev/%s\n", devname(buf.st_rdev, S_IFCHR));
printf("fdevname is /dev/%s\n", fdevname(fd));
The devname() function appeared in 4.4BSD. The fdevname() function
appeared in FreeBSD 8.0.
BSD February 22, 2005 BSD