mknod(2)       UNIX System V(Application Compatibility Package)        mknod(2)


NAME
      mknod - make a directory, or a special or ordinary file

SYNOPSIS
      #include <sys/types.h>
      #include <osfcn.h>
      #include <sys/stat.h>

      int mknod (const char *path, modet mode, devt dev);

DESCRIPTION
      mknod creates a new file named by the path name pointed to by path.  The
      file type and permissions of the new file are initialized from mode.

      The file type is specified in mode by the SIFMT bits, which must be set
      to one of the following values:

         SIFIFO   fifo special
         SIFCHR   character special
         SIFDIR   directory
         SIFBLK   block special
         SIFREG   ordinary file
         SIFNAM   name special file

      The file access permissions are specified in mode by the 0007777 bits,
      and may be constructed by an OR of the following values:
    SISUID   04000   Set user ID on execution.
    SISGID   020#0   Set group ID on execution if # is 7, 5, 3, or 1
                      Enable mandatory file/record locking if # is 6, 4, 2, or 0
    SISVTX   01000   Save text image  after execution.
    SIRUSR   00400   Read by owner.
    SIWUSR   00200   Write by owner.
    SIXUSR   00100   Execute (search if a directory) by owner.
    SIRWXG   00070   Read, write, execute by group.
    SIRGRP   00040   Read by group.
    SIWGRP   00020   Write by group.
    SIXGRP   00010   Execute by group.
    SIRWXO   00007   Read, write, execute  (search) by others.
    SIROTH   00004   Read by others.
    SIWOTH   00002   Write by others
    SIXOTH   00001   Execute by others.

      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.
      However, if the SISGID bit is set in the parent directory, then the
      group ID of the file is inherited from the parent.  If the group ID of
      the new file does not match the effective group ID or one of the
      supplementary group IDs, the SISGID bit is cleared.

      Values of mode other than those above are undefined and should not be
      used.  The access permission bits of mode are modified by the process's
      file mode creation mask:  all bits set in the process's file mode


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mknod(2)       UNIX System V(Application Compatibility Package)        mknod(2)


      creation mask are cleared [see umask(2)].  For block and character
      special files, dev is the special file's device number.  For name special
      files, dev is the file type of the name file, either a XENIX shared data
      file or a XENIX semaphore.  Otherwise, dev is ignored.  See mkdev(3C).

      mknod may be invoked only by the privileged user for file types other
      than FIFO special.

      mknod fails and creates no new file if one or more of the following are
      true:

      EEXIST              The named file exists.

      EINVAL              Invalid arg value.

      EFAULT              path points outside the allocated address space of
                          the process.

      ELOOP               Too many symbolic links were encountered in
                          translating path.

      EMULTIHOP           Components of path require hopping to multiple remote
                          machines.

      ENAMETOOLONG        The length of the path argument exceeds {PATHMAX},
                          or the length of a path component exceeds {NAMEMAX}
                          while (_POSIXNOTRUNC) is in effect.

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

      ENOENT              A component of the path prefix does not exist or is a
                          null pathname.

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

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

      ENOSPC              No space is available.

      EINTR               A signal was caught during the mknod system call.

      ENOLINK             path points to a remote machine and the link to that
                          machine is no longer active.

SEE ALSO
      creatsem(2), sdget(2)
      chmod(2), exec(2), umask(2), mkfifo(3C), stat(5) in the Programmer's
      Reference Manual
      fs(4) in the System Administrator's Reference Manual
      mkdir(1) in the User's Reference Manual


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mknod(2)       UNIX System V(Application Compatibility Package)        mknod(2)


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.

NOTES
      If mknod creates a device in a remote directory using Remote File
      Sharing, the major and minor device numbers are interpreted by the
      server.

      Semaphore files should be created with the creatsem system call.  Shared
      data files should be created with the sdget system call.











































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