How to create a temporary file in Linux
1.0 Temporary Files Quite often, we need temporary files in our programs. Some intermediate data needs to be stored and the file can be discarded when the process terminates. There…
Error while executing the dig command
1.0 Error While executing the dig command, the sendmsg() failed: Operation not permitted error was printed. $ dig example.com ../../../../lib/isc/unix/net.c:581: sendmsg() failed: Operation not permitted ../../../../lib/isc/unix/net.c:581: sendmsg() failed: Operation not…
Find user login history – last and lastb commands in Linux
1.0 last and lastb The last command gives a chronological list of user logins in a Linux system for a period of time. The lastb commands gives a similar list…
Cut command in Linux
1.0 cut The cut command cuts sections of each line of input files and writes it on its standard output. It is mostly used for taking out a few columns…
tr command in Linux
1.0 tr The tr command is a filter which reads the standard input, translates or deletes characters and writes on its standard output. The tr command syntax is, tr [OPTION]...…
uniq command in Linux
1.0 uniq The uniq command is a filter for finding unique lines in input. It reads input, suppresses duplicates and prints unique lines in its output. Used with the -D…
sort command in Linux
1.0 Sort The sort command is for sorting lines in text files. For example, if we have a file names, we can sort it with the sort command, $ cat…
grep Command in Linux
1.0 grep grep is a program for searching a given string pattern in files. It searches the files for the pattern and prints the lines that contain strings matching the…
Shell Scripting Tutorial
1.0 Shell Script bash is the commonly used shell in GNU-Linux. bash can be run interactively, as a login shell or as an interactive process from a terminal emulator like…
An Introduction to Shell in Linux
1.0 SHELL A shell provides a user interface to a computer system. There are two types of shells, the command line interface (CLI) and the graphical user interface (GUI). In…