Top Document: comp.sys.hp.hpux FAQ Previous Document: 8.41 Where can I look up HP part numbers? Next Document: 8.43 Why is tail's output truncated for large amounts of input? See reader questions & answers on this topic! - Help others by sharing your knowledge Prior to 11.11, HP-UX did not come with the special device file /dev/zero. However, it is possible to create one in 11.0 using the following command: # mknod /dev/zero c 3 4 Of course, use of the device file on an 11.0 system is unsupported by HP. In conjunction with the dd command, /dev/zero can be used to fill a file with a given number of the '\0' (nul) character. For example, to create a 1 MB file named "foo" full of nul characters, use the command: $ dd bs=1024k count=1 if=/dev/zero of=foo Note the same thing can be accomplished in 10.x using the prealloc(1) command as follows: $ prealloc foo 1048576 Note, filling a file with zeroes is not a secure way to wipe file data from disk. For this, you must use a utility such as 'shred', which is part of the GNU fileutils package. A device file with slightly similar behavior to /dev/zero can be created on 10.x as follows: # mknod /dev/full c 3 3 Reading from this device will always succeed and report that the requested number of bytes were read. However, no data will actually be copied to the read buffer. User Contributions:Top Document: comp.sys.hp.hpux FAQ Previous Document: 8.41 Where can I look up HP part numbers? Next Document: 8.43 Why is tail's output truncated for large amounts of input? Single Page [ Usenet FAQs | Web FAQs | Documents | RFC Index ] Send corrections/additions to the FAQ Maintainer: hpux.faq@gmail.com
Last Update March 27 2014 @ 02:11 PM
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