- List the files in current directory sorted by size ?
- ls -l | grep ^- | sort -nr
- List the hidden files in current directory ?
- ls -a1 | grep "^\."
- Delete blank lines in a file ?
- cat sample.txt | grep -v ‘^$’ > new_sample.txt
- Search for a sample string in particular files ?
- grep .Debug. *.conf
Here grep uses the string .Debug. to search in all files with extension..conf. under current directory.
- Display the last newly appending lines of a file during appendingdata to the same file by some processes ?
- tail .f Debug.log
Here tail shows the newly appended data into Debug.log by some processes/user.
- Display the Disk Usage of file sizes under each directory in currentDirectory ?
- du -k * | sort .nr (or) du .k . | sort -nr
- Change to a directory, which is having very long name ?
- cd CDMA_3X_GEN*
Here original directory name is . CDMA_3X_GENERATION_DATA..
- Display the all files recursively with path under current directory ?
- find . -depth -print
- Set the Display automatically for the current new user ?
- export DISPLAY=`eval ‘who am i | cut -d"(" -f2 | cut
Here in above command, see single quote, double quote, grave ascent is used. Observe carefully.
- Display the processes, which are running under yourusername ?
- ps .aef | grep gould
Here, gould is the username.
- List some Hot Keys for bash shell ? - Ctrl+l . Clears the Screen. Ctrl+r . Does a search in previously given commands in shell. Ctrl+u -
Clears the typing before the hotkey. Ctrl+a . Places cursor at the beginning of the command at shell. Ctrl+e . Places cursor at the end of the command at shell. Ctrl+d . Kills the shell. Ctrl+z .
Places the currently running process into background.
- Display the files in the directory by file size ?
- ls .ltr | sort .nr .k 5
- How to save man pages to a file ?
- man <command> | col .b > <output-file>
Example : man top | col .b > top_help.txt
- How to know the date & time for . when script is executed ?
- Add the following script line in shell script.eval echo "Script is executed at `date`" >> timeinfo.inf
Here, .timeinfo.inf. contains date & time details ie., when script is executed and history related to execution.
- How do you find out drive statistics ?
- iostat -E
Display disk usage in Kilobytes ?
- du -k
Display top ten largest files/directories ?
- du -sk * | sort -nr | head
- How much space is used for users in kilobytes ?
- quot -af
- How to create null file ?
- cat /dev/null > filename1
- Access common commands quicker ?
- ps -ef | grep -i $@
- Display the page size of memory ?
- pagesize -a
- Display Ethernet Address arp table ?
- arp -a
- Display the no.of active established connections to localhost ?
- netstat -a | grep EST
- Display the state of interfaces used for TCP/IP traffice ?
- netstat -i
- Display the parent/child tree of a process ?
- ptree <pid>
Example: ptree 1267
- Show the working directory of a process ?
- pwdx <pid>
Example: pwdx 1267
- Display the processes current open files ?
- pfiles <pid>
Example: pfiles 1267
- Display the inter-process communication facility status ? - ipcs
- Display the top most process utilizing most CPU ?
- top .b 1
- Alternative for top command ? - prstat -a