I read the
mknod man page, which is (as far as I can tell) what you would use to make a character device like
/dev/zero, but I don't see how you would get it to yield an infinite stream of zero bits (or another pattern). What is the procedure for creating such character devices?
I read the
mknod does is associate a device file with a device driver. There are device drivers that implement interaction with actual devices, and there are device drivers that just react to read-write requests in useful ways. If you want to you can sit down and write a driver that returns the lyrics of the Star Spangeled Banner. But it's a matter of coding, not finding the right arguments for
If you just want to re-create the
/dev/zero abilities but with a character other than zero/null, you can use
tr to change all the zero's ("\000" in octal) into something else.
So to spit out an endless stream of "a"s for example, you could do:
cat /dev/zero | tr "\000" "\141" | head -c 20 aaaaaaaaaaaaaaaaaaaa
Or skip the cat and output an M's worth (1024*1024) with
head -c 1M /dev/zero |tr "\000" "\141"
"\141" being the "a" character.
See this site http://www.asciitable.com/ for a quick short page of ASCII - Octal codes. It's actually this image here:
(I know, old "solved" question, but I found it while searching for an endless stream of different characters, so this "solves" the "how to make /dev/one or /dev/[different character]" problem.)