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 4.16 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)