diff options
Diffstat (limited to 'lib/libc/gen/devname.3')
| -rw-r--r-- | lib/libc/gen/devname.3 | 26 |
1 files changed, 24 insertions, 2 deletions
diff --git a/lib/libc/gen/devname.3 b/lib/libc/gen/devname.3 index c05d0ba..7ff31c7 100644 --- a/lib/libc/gen/devname.3 +++ b/lib/libc/gen/devname.3 @@ -43,6 +43,10 @@ .Fn devname "dev_t dev" "mode_t type" .Ft char * .Fn devname_r "dev_t dev" "mode_t type" "char *buf" "int len" +.Ft char * +.Fn fdevname "int fd" +.Ft char * +.Fn fdevname_r "int fd" "char *buf" "int len" .Sh DESCRIPTION The .Fn devname @@ -69,11 +73,24 @@ and .Fa type in a human-readable format. .Pp +The +.Fn fdevname +and +.Fn 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. +.Pp .Fn devname -returns the name stored in a static buffer which will be overwritten +and +.Fn fdevname +return the name stored in a static buffer which will be overwritten on subsequent calls. .Fn devname_r -takes a buffer and length as argument to avoid this problem. +and +.Fn fdevname_r +take a buffer and length as argument to avoid this problem. .Sh EXAMPLES .Bd -literal -compact int fd; @@ -83,6 +100,7 @@ char *name; fd = open("/dev/tun"); fstat(fd, &buf); printf("devname is /dev/%s\en", devname(buf.st_rdev, S_IFCHR)); + printf("fdevname is /dev/%s\en", fdevname(fd)); .Ed .Sh SEE ALSO .Xr stat 2 @@ -91,3 +109,7 @@ The .Fn devname function appeared in .Bx 4.4 . +The +.Fn fdevname +function appeared in +.Fx 8.0 . |
