freebsd man page for fdevname_r

DEVNAME(3)						   BSD Library Functions Manual 						DEVNAME(3)

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
", devname(buf.st_rdev, S_IFCHR));
	     printf("fdevname is /dev/%s
", fdevname(fd));

SEE ALSO
     stat(2)

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

BSD
								 February 22, 2005							       BSD