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DEVNAME(3)             FreeBSD Library Functions Manual             DEVNAME(3)

     devname - get device name

     Standard C Library (libc, -lc)

     #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);

     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.

     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));


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

FreeBSD 11.1-RELEASE-p4        February 22, 2005       FreeBSD 11.1-RELEASE-p4
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