On Fri, 22 Dec 2000, rpjday wrote:
> On Fri, 22 Dec 2000, David Brett wrote:
>
> > I am trying to pipe to ping without success.
> >
> > awk '{print$1} testfiles | ping -nc 1
> >
> > testfile is
> >
> > 10.1.1.1 server1
> > 10.1.1.2 server2
> >
> > Any ideas why I can't pipe to ping?
>
> perhaps because, according to ping, it doesn't accept hostnames
> on standard input. also, it doesn't *appear* to accept multiple
> arguments.
>
> check the man page.
>
> rday
>
Not really. The first part of his command should take care of that and
pass only the first field to 'ping'. The problem is rather with the way
the pipe works in UNIX and Linux. In this case, the output of
'awk '{print$1}' testfiles' is the standard input (stdin) to 'ping'. The
only problem is that 'ping' does not take standard input this way. You
should use the 'xargs' command and that should fix the problem, as in:
awk '{print$1}' testfiles | xargs ping -nc 1
Basically, 'xargs' takes the standard input passed through the pipe and
sort of pastes it to the end of the 'ping' command. Check the manual page
for a more technical explanation.
------------------------------------------------------
Nitebirdz
------------------------------------------------------
Thus spake the master programmer:
"You can demonstrate a program for a corporate
executive, but you can't make him computer literate."
_______________________________________________
Redhat-list mailing list
[EMAIL PROTECTED]
https://listman.redhat.com/mailman/listinfo/redhat-list
