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Homework and Emergencies Homework & Coursework Questions VM trap may work differently than a pure install trap. Post 302809649 by newuser45 on Monday 20th of May 2013 10:14:40 AM
Old 05-20-2013
Quote:
Originally Posted by bakunin
I pasted the quoted code into a file and ran it and - to my surprise - it worked. I would have expected this:

Code:
        count=$[ count + 1]

to caue problems, it "just doesn't seem right", but then, i use Korn Shell most of the times and avoid bash like the plague. I would have written:

Code:
        (( count += 1 ))

which should do the same and is POSIXly correct (notice the spaces around "((" and "))", they are necessary), but: never argue with success, yours obviously works.

One thing i noticed, though, was: as soon as i pressed "CTRL-C" the trap was executed but the "sleep 10" was interrupted and then skipped. Pressing CTRL-C often enough let me get through with the script in less than half a minute, whereas 10x 10 seconds of sleeping should have taken 1min 40sec (plus some for the rest).

So, probably there is something with your setup. I have no idea what that would be, though. I tried in an XTerm on Fedora without any real changes and it worked as expected.

I hope this helps.

bakunin
I just wanted to acknowledge your post bakunin. I'm not at a machine now but I'd like to not that when you say, 'sleep 10 was interrupted', that makes sense.

i am familiar with the += accumulator from Java, and haven't tried this syntax yet. So I consider this a step in the positive direction. In addition, I haven't tried XTerm yet either. I have my fingers crossed that this will make a difference. I'm really a hardware guy and in my experience, this is is a display issue. I think that my instructor, you, and myself agree that this has something to do with the way I'm setup, and a possibility of doing this in a virtual environment.

I thought I was doing myself a favor by running VirtualBox so that I could have a couple of Linux distributions and Windows Server 2008 r2 running all under the same umbrella. I haven't tried an actual install yet becuase I just didn't have time, and that's really the next step, besides trying to talk it out here.

I really appreciate your reply.
 
Test Your Knowledge in Computers #399
Difficulty: Medium
The 11i v2 release of HP-UX introduced kernel-based intrusion detection, strong random number generation, stack buffer overflow protection, security partitioning, role-based access management, and various open-source security tools.
True or False?

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SLEEP(3)						     Linux Programmer's Manual							  SLEEP(3)

NAME
sleep - Sleep for the specified number of seconds SYNOPSIS
#include <unistd.h> unsigned int sleep(unsigned int seconds); DESCRIPTION
sleep() makes the calling thread sleep until seconds seconds have elapsed or a signal arrives which is not ignored. RETURN VALUE
Zero if the requested time has elapsed, or the number of seconds left to sleep, if the call was interrupted by a signal handler. CONFORMING TO
POSIX.1-2001. BUGS
sleep() may be implemented using SIGALRM; mixing calls to alarm(2) and sleep() is a bad idea. Using longjmp(3) from a signal handler or modifying the handling of SIGALRM while sleeping will cause undefined results. SEE ALSO
alarm(2), nanosleep(2), signal(2), signal(7) COLOPHON
This page is part of release 3.27 of the Linux man-pages project. A description of the project, and information about reporting bugs, can be found at http://www.kernel.org/doc/man-pages/. GNU
2010-02-03 SLEEP(3)

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