UNIX Interview Questions

If all you want to do is get rid of that file, as I did, just save a known file, like a dummy text file, with that same name and overwrite the existing file. I replaced my errant directory file with a...

When a file or directory is created the default permisions inherited .they arefor files :666for dir: 777Actually it is not the file permission .the "umask" value is subtracted from these def...

Kill -3 pid is used to create thread dump for the process id. This is basically used for troubleshooting and to understand what went wrong with the above process. Suppose some node of weblogic is not ...

Kill-3 pid tells the compiler to kill the process with the process id 3.

When kill -3 command is executed, it will quit from executing the process and additionally it will dump core for that process mentioned with pid.

022 is the number of mask code ee@.

cp [a]* /export/home/

cp ~/a* .

By using "TOP"command we can see the CPU utilization. also u can ping the "sar" command

TOP command in UNIX is used to know about CPU utilization

use ::: chown command

who;echo "Total number of users: "`who|wc -l`

Ans for question 1

echo `who`\n the number of users logged in is `who | wc -l`

#!/bin/ksh +x


df -kl|grep "<8[0-9]%>" > dfout.log
df -kl|grep "<9[0-9]%>" >> dfout.log
df -kl|grep "100%" >> dfout.log

echo $http_proxy

ifconfig

Kernel - The kernel is the main component of most computer operating systems. - It is a bridge between applications and the actual data processing done at the hardware level - The kernel is the heart ...

Unix was developed using ‘C’ Language. Unix was the foundation on which Linux was built. Unix has Character based environment while Linux has Graphical as well as Character based environment. Unix has...

In computer storage, logical volume management or LVM provides a method of allocating space on mass-storage devices that is more flexible than conventional partitioning schemes. In particular, a volum...

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we need root access to kill the process.But have to check before killing process whether it is using by any user and importance of that process.

The wait command man page simply states that it pauses script execution until a specified process ID completes.

The man page for the sleep command is a single line stating that it causes a script to pause for specified period of time.

14.Depend on utilization% of sys,wait and usr a) If sys is showing high value, there may be more kernel system calls b) If usr is high ,the application space is using CPU for their operation c) If wa...

The '.' indicates the current directory. If the PATH environment variable is not set to look for commands in current directory, you need to use a './' before executing any command in the current directory.

2.at a fixed location on the disk

At a fixed address in memory location.

NFS supports two types of mounts -- hard mounts and soft mounts. If a mount is a hard mount, an NFS request affecting any part of the mounted resource is issued repeatedly until the request is satisfi...

If a remote file system is hard mounted on a server, in some case the server is down,While boot the server checks the hard mount of the remote file sytem the boot, if remote systm also down, at the pa...

Kernel is base foundation of operating system .The kernel provide services such as hardware and software interaction
and memory management. Efficiency of operating system is depend on efficiency of kernel.

Unix operating system derived into three different levels and the inner most level is Kernel. Who is the sole responsible of all the activites as scheduler, memory manager etc. The outmost level is Shell which connect to end user with the Kernel.

1 & 3

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