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NULL(4)			   Linux Programmer's Manual		       NULL(4)



NAME
       null, zero - data sink

DESCRIPTION
       Data written to the /dev/null and /dev/zero special files is discarded.

       Reads  from  /dev/null always return end of file (i.e., read(2) returns
       0), whereas reads from /dev/zero always return  bytes  containing  zero
       ('\0' characters).

       These devices are typically created by:

	      mknod -m 666 /dev/null c 1 3
	      mknod -m 666 /dev/zero c 1 5
	      chown root:root /dev/null /dev/zero

FILES
       /dev/null
       /dev/zero

NOTES
       If these devices are not writable and readable for all users, many pro-
       grams will act strangely.

       Since Linux 2.6.31, reads from /dev/zero are interruptible by  signals.
       (This  change  was made to help with bad latencies for large reads from
       /dev/zero.)

SEE ALSO
       chown(1), mknod(1), full(4)

COLOPHON
       This page is part of release 4.10 of the Linux  man-pages  project.   A
       description  of	the project, information about reporting bugs, and the
       latest	 version    of	  this	  page,	   can	   be	  found	    at
       https://www.kernel.org/doc/man-pages/.



Linux				  2015-07-23			       NULL(4)