Updated: 2021/Apr/14

DEVNAME(3)                 Library Functions Manual                 DEVNAME(3)

NAME
     devname, devname_r - get device name

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     #include <stdlib.h>
     #include <sys/stat.h>

     char *
     devname(dev_t dev, mode_t type);

     int
     devname_r(dev_t dev, mode_t type, char *path, size_t len);

DESCRIPTION
     The devname() function returns a pointer to the static buffer with 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.  If no device matches the specified values, or no
     information is available, NULL is returned.

     The devname_r() function is a reentrant and thread-safe version of
     devname().  This function returns the device name by copying it into the
     path argument with up to len characters.  The path argument is always
     nul-terminated.

     The traditional display for applications when no device is found is the
     string "??".

RETURN VALUES
     If successful, devname() returns a pointer to a nul-terminated string
     containing the name of the device.  If an error occurs devname will
     return NULL.

     If successful, devname_r() places a nul-terminated string containing the
     name of the device in the buffer pointed to by path and returns 0.  If an
     error occurs devname_r() will return an error number from <sys/errno.h>
     indicating what went wrong.

FILES
     /var/run/dev.cdb  Device database file.

ERRORS
     The devname_r() function may fail if:

     [ENOENT]           The corresponding device does not exist.

     [ERANGE]           The passed buffer length is too short.

SEE ALSO
     stat(2), dev_mkdb(8)

HISTORY
     The devname function call appeared in 4.4BSD.

     The devname_r() function first appeared in NetBSD 6.0.

NetBSD 9.99                    September 9, 2017                   NetBSD 9.99