Visit Our UNIX and Linux User Community

Linux and UNIX Man Pages

Test Your Knowledge in Computers #269
Difficulty: Easy
Apple merged with NeXT in 1997, and subsequently, Steve Jobs became Apple's CEO again.
True or False?
Linux & Unix Commands - Search Man Pages

mknod(2) [mojave man page]

MKNOD(2)						      BSD System Calls Manual							  MKNOD(2)

NAME
mknod -- make a special file node SYNOPSIS
#include <sys/stat.h> int mknod(const char *path, mode_t mode, dev_t dev); DESCRIPTION
The device special file path is created with the major and minor device numbers extracted from mode. The access permissions of path are con- strained by the umask(2) of the parent process. If mode indicates a block or character special file, dev is a configuration-dependent specification of a character or block I/O device and the superblock of the device. If mode does not indicate a block special or character special device, dev is ignored. mknod() requires super-user privileges. RETURN VALUES
Upon successful completion, a value of 0 is returned. Otherwise, a value of -1 is returned and errno is set to indicate the error. ERRORS
mknod() will fail and the file will be not created if: [EACCES] Search permission is denied for a component of the path prefix. [EACCES] Write permission is denied for the parent directory. [EDQUOT] The directory in which the entry for the new node is being placed cannot be extended; the user's quota of disk blocks on the file system containing the directory has been exhausted. [EDQUOT] The user's quota of inodes for the file system on which the node is being created has been exhausted. [EEXIST] The named file exists. [EFAULT] Path points outside the process's allocated address space. [EINVAL] One or more of the arguments is invalid. [EIO] An I/O error occurs while making the directory entry or allocating the inode. [ELOOP] Too many symbolic links were encountered in translating the pathname. This is taken to be indicative of a looping sym- bolic link. [ENAMETOOLONG] A component of a pathname exceeds {NAME_MAX} characters or an entire path name exceeds {PATH_MAX} characters. [ENOENT] A component of the path prefix does not exist or path is an empty string. [ENOSPC] The directory in which the entry for the new node is being placed cannot be extended, because there is no space left on the file system containing the directory. [ENOSPC] There are no free inodes on the file system on which the node is being created. [ENOTDIR] A component of the path prefix is not a directory. [EPERM] The process's effective user ID is not super-user. [EROFS] The created node would reside on a read-only file system. LEGACY SYNOPSIS
#include <unistd.h> The include file has changed. SEE ALSO
chmod(2), stat(2), umask(2), compat(5) HISTORY
A mknod() function call appeared in Version 6 AT&T UNIX. 4th Berkeley Distribution June 4, 1993 4th Berkeley Distribution

Check Out this Related Man Page

MKNOD(2)						      BSD System Calls Manual							  MKNOD(2)

NAME
mknod, mknodat -- make a special file node LIBRARY
Standard C Library (libc, -lc) SYNOPSIS
#include <sys/stat.h> int mknod(const char *path, mode_t mode, dev_t dev); int mknodat(int fd, const char *path, mode_t mode, dev_t dev); DESCRIPTION
The file system node path is created with the file type and access permissions specified in mode. The access permissions are modified by the process's umask value. If mode indicates a block or character special file, dev is a configuration dependent specification denoting a particular device on the sys- tem. Otherwise, dev is ignored. The mknod() system call requires super-user privileges. The mknodat() system call is equivalent to mknod() except in the case where path specifies a relative path. In this case the newly created device node is created relative to the directory associated with the file descriptor fd instead of the current working directory. If mknodat() is passed the special value AT_FDCWD in the fd parameter, the current working directory is used and the behavior is identical to a call to mknod(). RETURN VALUES
The mknod() function returns the value 0 if successful; otherwise the value -1 is returned and the global variable errno is set to indicate the error. ERRORS
The mknod() system call will fail and the file will be not created if: [ENOTDIR] A component of the path prefix is not a directory. [ENAMETOOLONG] A component of a pathname exceeded 255 characters, or an entire path name exceeded 1023 characters. [ENOENT] A component of the path prefix does not exist. [EACCES] Search permission is denied for a component of the path prefix. [ELOOP] Too many symbolic links were encountered in translating the pathname. [EPERM] The process's effective user ID is not super-user. [EIO] An I/O error occurred while making the directory entry or allocating the inode. [ENOSPC] The directory in which the entry for the new node is being placed cannot be extended because there is no space left on the file system containing the directory. [ENOSPC] There are no free inodes on the file system on which the node is being created. [EDQUOT] The directory in which the entry for the new node is being placed cannot be extended because the user's quota of disk blocks on the file system containing the directory has been exhausted. [EDQUOT] The user's quota of inodes on the file system on which the node is being created has been exhausted. [EROFS] The named file resides on a read-only file system. [EEXIST] The named file exists. [EFAULT] The path argument points outside the process's allocated address space. [EINVAL] Creating anything else than a block or character special file (or a whiteout) is not supported. In addition to the errors returned by the mknod(), the mknodat() may fail if: [EBADF] The path argument does not specify an absolute path and the fd argument is neither AT_FDCWD nor a valid file descriptor open for searching. [ENOTDIR] The path argument is not an absolute path and fd is neither AT_FDCWD nor a file descriptor associated with a directory. SEE ALSO
chmod(2), mkfifo(2), stat(2), umask(2) STANDARDS
The mknodat() system call follows The Open Group Extended API Set 2 specification. HISTORY
The mknod() function appeared in Version 6 AT&T UNIX. The mknodat() system call appeared in FreeBSD 8.0. BSD
January 16, 2011 BSD

Featured Tech Videos