mknod(8) System Manager's Manual mknod(8)NAME
mknod - Creates a special file
SYNOPSIS
/usr/sbin/mknod special_file [ b major_device# minor_device# | c major_device# minor_device#]
/usr/sbin/mknod filename p
DESCRIPTION
The mknod command makes a directory entry. The first argument is the name of the special device file. Select a name that is descriptive
of the device.
The mknod command has two forms. In the first form, the second argument is the b or c flag. The last two arguments are numbers specifying
the major_device, which helps the operating system find the device driver code, and the minor_device, the unit drive, or line number, which
may be either decimal or octal.
The assignment of major device numbers is specific to each system. You can determine the device numbers by examining the conf.c system
source file. If you change the contents of the conf.c file to add a device driver, you must rebuild the kernel.
In the second form of mknod, you use the p flag to create named pipes (FIFOs).
Only the superuser can create a character or device special file.
FLAGS
Indicates that the special file corresponds to a block-oriented device (disk or tape) Indicates that the special file corresponds to a
character-oriented device Creates named pipes (FIFOs)
EXAMPLES
To create the special file for a new drive, /dev/disk/dsk20, with a major device number of 1 and a minor device number of 2, enter: mknod
/dev/disk/dsk20 b 1 2 This command creates the special file, /dev/disk/dsk20, which is a block special file with major device number 1
and minor device number 2. To create a pipe named fifo, enter: mknod fifo p This command creates the pipe fifo, which is not necessarily
in the current directory.
FILES
Specifies the command path Specifies the system device numbers specification file delim off
mknod(8)
Check Out this Related Man Page
mknod(1M) System Administration Commands mknod(1M)NAME
mknod - make a special file
SYNOPSIS
mknod name b major minor
mknod name c major minor
mknod name p
DESCRIPTION
mknod makes a directory entry for a special file.
OPTIONS
The following options are supported:
b Create a block-type special file.
c Create a character-type special file.
p Create a FIFO (named pipe).
OPERANDS
The following operands are supported:
major The major device number.
minor The minor device number; can be either decimal or octal. The assignment of major device numbers is specific to each system. You
must be the super-user to use this form of the command.
name A special file to be created.
USAGE
See largefile(5) for the description of the behavior of mknod when encountering files greater than or equal to 2 Gbyte ( 2**31 bytes).
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
+-----------------------------+-----------------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+-----------------------------+-----------------------------+
|Availability |SUNWcsu |
+-----------------------------+-----------------------------+
SEE ALSO ftp(1), in.ftpd(1M), mknod(2), symlink(2), attributes(5), largefile(5)NOTES
If mknod(2) is used to create a device, the major and minor device numbers are always interpreted by the kernel running on that machine.
With the advent of physical device naming, it would be preferable to create a symbolic link to the physical name of the device (in the
/devices subtree) rather than using mknod.
SunOS 5.10 16 Sep 1996 mknod(1M)
Hi !
I had a verry simple question to ask...
In unix when we create pipes.. the unnamed pipes that is...
is there any way to access those pipes outside the code ?
Another thing.. do sockets have an entry in the inode table ?
TIA,
Devyani. (1 Reply)
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Can someone please tell me what the command mknod does and what it's syntax is? I can't find it in my "Unix for dummies" book or "Unix in s nutshell". I found it in an existing script that I want to copy, but I want to understand what I am doing. The script is going to do a full export of an... (3 Replies)
Hi...
this is the situation.
I have a server with redhat Advance Server 3 and the operating system is installed in /dev/sda disk... when i include new Luns dinamically they take the following special files /dev/sdb and /dev/sdc.... ok.. until now is everything ok... but the problem begins... (2 Replies)
I'm trying to use the "mknod" call in C to create a clone of /dev/null. I am stumped as to the final parameter I should provide to "mknod()". I am supposed to give it a type dev_t, which specifies a major & minor number. I want to specify major 3, minor 1, but how can I do this?
dev_t seems to... (2 Replies)
Hi,
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Something (I'm still trying to find out what) has clobbered our /dev/null and made it into an ordinary file. I know I need to recreate it with mknod, but I'm unsure what the major and minor device numbers should be - I know enough to know that they vary on different systems and I've seen 1 3, 2 2,... (4 Replies)
I'm not sure whether or not this question really belongs in this forum and will accept rebuke should I have mistakenly put it in the wrong place (hopefully the rebuke will be accompanied by an answer, though)
I wish to implement named pipe communication between two process using MKS Toolkit. I... (2 Replies)
Hello All,
Friends i know mknod with -p option is used to create FIFO special file.:p
But i want to know some circumstance/scenario where these are used.:wall:
Actually i want to know where i can use it in real time.
Please advise.:) (3 Replies)
Hi Guys,
On my AIX server , I have this file "mknod" present in the /etc/ directory. When i try opening it , I dont find
any ascii characters. It shows some encryption/binary format which is not readable. Is it any executable ? what is the
purpose of having this file in etc folder? what if... (2 Replies)