MKNOD(2)MKNOD(2)NAMEmknod - make a directory, or a special or ordinary file
C SYNOPSIS
#include <sys/types.h>
#include <sys/stat.h>
int mknod (const char *path, mode_t mode, dev_t dev);
DESCRIPTIONmknod creates a new file named by the path name pointed to by path. The
mode of the new file (including file type bits) is initialized from mode.
The value of the file type bits which are permitted with this system call
are those listed below. The other types listed in sys/stat.h are made
with other system calls, or are not supported by this operating system.
S_IFIFO fifo special
S_IFCHR character special
S_IFBLK block special
S_IFREG ordinary file
All other mode bits are interpreted as described in chmod(2).
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
or the group ID of the directory in which the file is being created.
This is determined as follows:
If the underlying filesystem was mounted with the BSD file creation
semantics flag [see fstab(4)] or the S_ISGID bit is set [see
chmod(2)] on the parent directory, then the group ID of the new file
is set to the group ID of the parent directory, otherwise it is set
to the effective group ID of the calling process.
Values of mode other than those above are undefined and should not be
used. 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)]. If mode indicates a block or character
special file, dev is a configuration-dependent specification of a
character or block I/O device. If mode does not indicate a block special
or character special device, dev is ignored.
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.
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MKNOD(2)MKNOD(2)
[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 allocated address space of the
process.
[ENAMETOOLONG] The length of the path argument exceeds {PATH_MAX}, or a
pathname component is longer than {NAME_MAX}.
[ENOSPC] The directory in which the entry for the new directory
is being placed cannot be extended because there is no
space left on the file system containing the directory
or the new directory cannot be created because there is
no space left on the file system that will contain the
directory or there are no free inodes on the file system
on which the directory is being created.
[EDQUOT] The directory in which the entry for the new node is
being placed cannot be extended either because the
user's quota of disk blocks on the file system
containing the directory has been exhausted or the
user's quota of inodes on the file system on which the
node is being created has been exhausted.
[EINVAL] If you create files of the type fifo special, character
special, or block special on an NFS-mounted file system.
SEE ALSOmkdir(1), chmod(2), exec(2), mkdir(2), umask(2), fstab(4)DIAGNOSTICS
Upon successful completion a value of 0 is returned. Otherwise, a value
of -1 is returned and errno is set to indicate the error.
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