Differences between current version and revision by previous author of mknod(2).
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| Newer page: | version 2 | Last edited on Monday, March 10, 2003 3:23:53 pm | by PerryLorier | |
| Older page: | version 1 | Last edited on Tuesday, June 4, 2002 12:23:43 am | by perry | Revert |
@@ -1,194 +1,58 @@
-MKNOD
-!!!MKNOD
-NAME
-SYNOPSIS
-DESCRIPTION
-RETURN VALUE
-ERRORS
-CONFORMING TO
-NOTES
-SEE ALSO
-----
!!NAME
-
-
mknod - create a special or ordinary file
!!SYNOPSIS
+ #include <sys/types.h>
+ #include <sys/stat.h>
+ #include <fcntl.h>
+ #include <unistd.h>
+ __int mknod(const char *__''pathname''__, mode_t __''mode''__, dev_t__'' dev''__);__
-__#include
-__''pathname''__, mode_t__ ''mode''__, dev_t__ ''dev''__);
-__
!!DESCRIPTION
+mknod(2) attempts to create a filesystem node (file, device special file or named pipe) named ''pathname'', specified by ''mode'' and ''dev''.
+''mode'' specifies both the permissions to use and the type of node to be created.
-__mknod__ attempts to create
a filesystem node
(file,
-device special file or named pipe) named ''pathname'',
-specified by ''mode''
and ''dev''
.
+It should be
a combination
(using bitwise OR) of one of the
file types listed below
and the permissions for the new node
.
+The permissions are modified by the process's __umask__ in the usual way: the permissions of the created node are __(mode & ~umask)__.
-''mode'' specifies both the permissions to use and the
-node
to be created.
+The file
type should be one
of __S_IFREG__, __S_IFCHR__, __S_IFBLK__ and __S_IFIFO__
to specify a normal file (which will
be created empty), character special file, block special file or FIFO (named pipe), respectively, or zero, which will create a normal file
.
-
-It should be a combination (using bitwise OR) of one of the
-file types listed below and the permissions for the new
-node.
-
-
-The permissions are modified by the process's __umask__
-in the usual way: the permissions of the created node are
-__(mode __.
-
-
-The file type should be one of __S_IFREG__,
-__S_IFCHR__, __S_IFBLK__ and __S_IFIFO__ to specify
-a normal file (which will be created empty), character
-special file, block special file or FIFO (named pipe),
-respectively, or zero, which will create a normal
-file.
-
-
-
-
-
+If the file type is __S_IFCHR__ or __S_IFBLK__ then ''dev'' specifies the major and minor numbers of the newly created device special file; otherwise it is
ignored.
+If ''pathname'' already exists, or is a symlink, this call fails with an [EEXIST] error.
-If ''pathname'' already exists
, or is a symlink, this
-call fails
with an EEXIST error
.
+The newly created node will be owned by the effective uid of the process.
If the directory containing the node has the set group id bit set
, or if the filesystem
is mounted
with BSD group semantics, the new node will inherit the group ownership from its parent directory; otherwise it will be owned by the effective gid of the process
.
-
-The newly created node will be owned by the effective uid of
-the process. If the directory containing the node has the
-set group id bit set, or if the filesystem is mounted with
-BSD group semantics, the new node will inherit the group
-ownership from its parent directory; otherwise it will be
-owned by the effective gid of the process.
!!RETURN VALUE
+mknod(2) returns zero on success, or -1 if an error occurred (in which case, ''errno'' is set appropriately).
-
-__mknod__ returns zero on success, or -1 if an error
-occurred (in which case, ''errno'' is set
-appropriately).
!!ERRORS
+;[EPERM]: ''mode'' requested creation of something other than a FIFO (named pipe), and the caller is not the superuser; also returned if the filesystem containing ''pathname'' does not support the type of node requested.
+;[EINVAL]: ''mode'' requested creation of something other than a normal file, device special file or FIFO.
+;[EEXIST]: ''pathname'' already exists.
+;[EFAULT]: ''pathname'' points outside your accessible address space.
+;[EACCES]: The parent directory does not allow write permission to the process, or one of the directories in ''pathname'' did not allow search (execute) permission.
+;[ENAMETOOLONG]: ''pathname'' was too long.
+;[ENOENT]: A directory component in ''pathname'' does not exist or is a dangling symbolic link.
+;[ENOTDIR]: A component used as a directory in ''pathname'' is not, in fact, a directory.
+;[ENOMEM]: Insufficient kernel memory was available.
+;[EROFS]: ''pathname'' refers to a file on a read-only filesystem.
+;[ELOOP]: Too many symbolic links were encountered in resolving ''pathname''.
+;[ENOSPC]: The device containing ''pathname'' has no room for the new node.
-
-__EPERM__
-
-
-''mode'' requested creation of something other than a
-FIFO (named pipe), and the caller is not the superuser; also
-returned if the filesystem containing ''pathname'' does
-not support the type of node requested.
-
-
-__EINVAL__
-
-
-''mode'' requested creation of something other than a
-normal file, device special file or FIFO.
-
-
-__EEXIST__
-
-
-''pathname'' already exists.
-
-
-__EFAULT__
-
-
-''pathname'' points outside your accessible address
-space.
-
-
-__EACCES__
-
-
-The parent directory does not allow write permission to the
-process, or one of the directories in ''pathname'' did
-not allow search (execute) permission.
-
-
-__ENAMETOOLONG__
-
-
-''pathname'' was too long.
-
-
-__ENOENT__
-
-
-A directory component in ''pathname'' does not exist or
-is a dangling symbolic link.
-
-
-__ENOTDIR__
-
-
-A component used as a directory in ''pathname'' is not,
-in fact, a directory.
-
-
-__ENOMEM__
-
-
-Insufficient kernel memory was available.
-
-
-__EROFS__
-
-
-''pathname'' refers to a file on a read-only
-filesystem.
-
-
-__ELOOP__
-
-
-Too many symbolic links were encountered in resolving
-''pathname''.
-
-
-__ENOSPC__
-
-
-The device containing ''pathname'' has no room for the
-new node.
!!CONFORMING TO
+SVr4 (but the call requires privilege and is thus not in POSIX), 4.4BSD. The Linux version differs from the SVr4 version in that it does not require root permission to
+create pipes, also in that no [EMULTIHOP], [ENOLINK], or [EINTR] error is documented.
-
-SVr4 (but the call requires privilege and is thus not in
-POSIX), 4.4BSD. The Linux version differs from the SVr4
-version in that it does not require root permission to
-create pipes, also in that no EMULTIHOP, ENOLINK, or EINTR
-error is documented.
!!NOTES
+POSIX 1003.1‐2001 says: "The only portable use of mknod() is to create a FIFO‐special file. If mode is not S_IFIFO or dev is not 0, the behavior of mknod() is unspecified."
+Under Linux, this call cannot be used to create directories or socket files, and cannot be used to create normal files by users other than the superuser. One should make directories with mkdir(2), and FIFOs with mkfifo(2).
-The Austin draft says:
-mknod__() is to create a FIFO-special file
. If
-''mode'' is not S_IFIFO or ''dev'' is not , the
-behavior
of __
mknod__
() is
-unspecified
.__
+There are many infelicities in the protocol underlying NFS
. Some
of these affect
mknod(2
).
-
-Under Linux, this call cannot be used to create directories
-or socket files, and cannot be used to create normal files
-by users other than the superuser. One should make
-directories with __mkdir__, and FIFOs with
-__mkfifo__.
-
-
-There are many infelicities in the protocol underlying NFS.
-Some of these affect __mknod__.
!!SEE ALSO
-
-
-
-
-
-
-
-----
+close(2), fcntl(2), mkdir(2), mount(2), open(2), read(2), socket(2), stat(2), umask(2), unlink(2), write(2), fopen(3), mkfifo(3)
