I want command to get Linux machine(amazon) external/public IP Address. I tried hostname -I and other commands from blogs and stackoverflow like and many more. But they all are giving me internal IP Address. Then I found some sites which provides API for this. Example : curl http://ipecho.net/plain; echo But …
Infinite while not working with os.execvp
I am programming in python which involves me implementing a shell in Python in Linux. I am trying to run standard unix commands by using os.execvp(). I need to keep asking the user for commands so I have used an infinite while loop. However, the infinite while loop doesn’t work. I have tried searching o…
Printing an integer with x86 32-bit Linux sys_write (NASM)
I’m new to this forum. I have a little experience with high-level languages (really little). Nearly one month ago I thought it would be a good idea to see how assembly worked so after choosing nasm (IA-32) on linux I started learning from a tutorial. Now, after ending it, I tried to write a simple progr…
How much does using htaccess files slow down website performance (especially with solid state disks)?
The Apache docs say (http://httpd.apache.org/docs/2.4/howto/htaccess.html), “You should avoid using .htaccess files completely if you have access to httpd main server config file. Using .htaccess files slows down your Apache http server. Any directive that you can include in a .htaccess file is better s…
__ldg causes slower execution time in certain situation
I posted this issue already yesterday, but wasnt well received, though I have solid repro now, please bear with me. Here are system specs: Tesla K20m with 331.67 driver, CUDA 6.0, Linux machine. Now I have a global memory read heavy application therefore I tried to optimize it using __ldg instruction on every…
Why aren’t glibc’s function addresses randomized when ASLR is enabled?
In trying to understand ASLR, I built this simple program: ALSR seems to be enabled: and I used GCC to compile the program: Every time I run this program, it prints the same address (0x400450). I would expect this program to print a different address each time if glibc is loaded at a random address. This is s…
kvm: module verification failed: signature and/or required key missing – tainting kernel
I’m using Ubuntu 14.04 LTS and kernel version 3.13.11.4. I’m trying to load patched KVM modules kvm and kvm-intel and I’m getting the following errors kvm: module verification failed: signature and/or required key missing – tainting kernel and kvm: module has bad taint, not creating tr…
Force no prompt in apt-get upgrade or apt-get dist-upgrade
I’m using AWS EC2 14.04 LTS and I’m trying to run command apt-get -y upgrade or apt-get -y dist-upgrade, however, I always get prompt like this: I tried following commands and none of them work and I still get above prompt: apt-get update && apt-get -y -o Dpkg::Options::=”–forc…
“Pixels out of bounds” error in IRAF
I am trying to do a PSF fitting on a fits image using SNOOPY (a point spread function fitter) and IRAF. I can open this image fine using imexam but when I select a point (a star or whatever) I get an error: It seems that what I am seeing and what IRAF is seeing (behind the scenes) are not
Python shell script open less with +F option
I have the following Python script, all seems to work how I want it to, except for the following: less opens with the option -F, this will follow the file like Tail would. to inspect (move through) the file the user has to ctrl + c to send an interrrupt. when sending the ctrl +c (interrupt) this gets send to