On Wed, May 25, 2005 at 11:28:04AM +0100, michael wrote:
> On Wed, 2005-05-25 at 12:00 +0200, Urs Thuermann wrote:
> > : > /etc/mtab
>
> what's the ':' do???
Nothing. At least hardly anything worth mentioning. See this snippet
from the bash manual:
#####
SHELL BUILTIN COMMANDS
: [arguments]
No effect; the command does nothing beyond expanding arguments and
performing any specified redirections. A zero exit code is returned.
#####
That also means it doesn't have any output. This empty output
is now redirected to /etc/mtab, making that file empty. You can try
other methods as well, e.g. 'cat /dev/null > /etc/mtab'.
maurits@mauritsvanrees:~$ echo "Hello World" > temp
maurits@mauritsvanrees:~$ cat temp
Hello World
maurits@mauritsvanrees:~$ : > temp
maurits@mauritsvanrees:~$ cat temp
maurits@mauritsvanrees:~$
Does anyone know any other uses for this ':' command?
HTH,
--
Maurits van Rees | http://maurits.vanrees.org/ [Dutch/Nederlands]
Public GnuPG key: keyserver.net ID 0x1735C5C2
"Let your advance worrying become advance thinking and planning."
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