NAME

mknod − make a directory, or a special or ordinary file

SYNOPSIS

#include <mknod.h>
int mknod (path, mode, dev)
char ∗path;
int mode;
dev_t dev;

HP-UX COMPATIBILITY

Level: HP-UX/RUN ONLY

Origin:
System V

DESCRIPTION

Mknod creates a new file named by the path name pointed to by path. The mode of the new file is initialized from mode, where the value of mode is interpreted as follows:

0170000 file type; one of the following:
0010000 fifo special
0020000 character special
0040000 directory
0060000 block special
0100000 or 0000000 ordinary file
0110000 network special
0004000 set user ID on execution
0002000 set group ID on execution
0001000 save text image after execution
0000777 access permissions; constructed from the following:
0000400 read by owner
0000200 write by owner
0000100 execute (search on directory) by owner
0000070 read, write, execute (search) by group
0000007 read, write, execute (search) by others

Values of mode other than those above are undefined and should not be used. 

The owner ID of the file is set to the effective user ID of the process.  The group ID of the file is set to the effective group ID of the process. 

The low-order 9 bits of mode are modified by the process’s file mode creation mask: all bits set in the process’s file mode creation mask are cleared.  See umask(2).

Dev is meaningful only if mode indicates a block or character special file, and is ignored otherwise.  It is an implementation and configuration dependent specification of a character or block I/O device.  A device name is created by using the makedev macro defined in mknod.h. The arguments to makedev are the major and minor device numbers, the value and interpretation of which are implementation dependent.  The result of makedev is an object of type dev_t. 

Mknod may be invoked only by the super-user for file types other than FIFO special. 

Mknod will fail and the new file will not be created if one or more of the following are true:

­[EPERM] The effective user ID of the process is not super-user. 

­[ENOTDIR] A component of the path prefix is not a directory. 

­[ENOENT] A component of the path prefix does not exist. 

­[EROFS] The directory in which the file is to be created is located on a read-only file system. 

­[EEXIST] The named file exists. 

­[EFAULT] Path points outside the process’s allocated address space. 

­[ENOENT] Path is null. 

­[EACCES] Path is in a directory that denies write permission, mode is for fifo special file, and the caller is not super-user. 

HARDWARE DEPENDENCIES

Series 200 and 500:
An additional value is available for network special files under file type.  Its value is 0110000.

Integral PC:
The super-user capabilities are provided to the normal user.

RETURN VALUE

Upon successful completion a value of 0 is returned.  Otherwise, a value of −1 is returned and errno is set to indicate the error. 

SEE ALSO

mkdir(1), chmod(2), mkdir(2), exec(2), umask(2), fs(5), mknod(5), mknod(8). 

Hewlett-Packard  —  last mod. May 11, 2021