Curses formatting

siffland has asked for the wisdom of the Perl Monks concerning the following question:

I have the following Perl script and it works just how I want it to. The only problem I have have is when executed each line of the output is tabbed (staggard) instead of left justified. This is the first time i have ever attempted to use the curses module. If there is another module that will work better let me know.

#!/usr/bin/perl

use Curses;
use Net::Ping;

@host_array = qw(fee fie foo quan);

initscr();
noecho();
cbreak();
nodelay(1);

while(1) {
  clear ();
  refresh();
  # High precision syntax (requires Time::HiRes)
  foreach $host (@host_array) {
    $p = Net::Ping->new();
    $p->hires();
    ($ret, $duration, $ip) = $p->ping($host, 5.5);
    printf("$host [ip: $ip] is down\n") unless $p->ping($host, 2);
    printf("$host [ip: $ip] is alive (packet return time: %.2f ms)\n",
+ 1000 * $duration) if $ret;
    $p->close();
  }
  sleep 2;
}
[download]

thanks, Sean

Comment on Curses formatting Download Code

Replies are listed 'Best First'.
Re: Curses formatting by Fletch (Bishop) on Jan 21, 2010 at 22:24 UTC
Your problem is that you're trying to intermix plain vanilla IO (printf) with curses. Curses expects you to do all output through it so that it can maintain a map of what's supposed to be on the screen. You'll want to use `addstr` rather than printing (although you certainly can use sprintf to format the text you display). The cake is a lie. The cake is a lie. The cake is a lie.	[reply] [d/l]
Re: Curses formatting by Khen1950fx (Canon) on Jan 21, 2010 at 22:54 UTC
Ah, got it. This should work: #!/usr/bin/perl use Curses; use Net::Ping; @host_array = qw(fee fie foo quan); initscr(); cbreak(); noecho(); clear(); refresh(); endwin(); while(1) { # High precision syntax (requires Time::HiRes) foreach my $host (@host_array) { $p = Net::Ping->new(); $p->hires(1); ($ret, $duration, $ip) = $p->ping($host, 5.5); printf("$host [ip: $ip] is down\n") unless $p->ping($host, 2); printf("$host [ip: $ip] is alive (packet return time: %.2f ms)\n", + 1000 * $duration) if $ret; $p->close(); } $p->close(); exit(0); } [download] Update: Deleted addstr.	[reply] [d/l]