linux

Linux: Software installation

Linux: Software installation

Software installation Good article: https://www.digitalocean.com/community/tutorials/package-management-basics-apt-yum-dnf-pkg First way (not recommended) compile the program from source code and copping the binaries to our system. Pros: non root user can install,...

Linux – program return code.

Linux – program return code.

And , or , does not matter... Return code of a given program is 0 if everything went OK and Not Zero if something went south. logical and && $ls -l someFileOrDir && echo OK logical or || $ls -l  nonExistedFile || echo ERR whenever a program returns...

Linux – STDIN STDOUT STDERR

Linux – STDIN STDOUT STDERR

STDIN Standart input stream (descriptor 0) - arguments that goes into a program. We can rearrange the output stream of one program to standard input stream of another program.(piping) $cat file_one | grep ^- | grep rwx | grep $2 (^ - lines starts with.. $ - line ends...

Basic linux commands II

Basic linux commands II

grep   (global regular expression print) $grep "failed*" -i log_file print all lines with the word "failed" + * (-i  ignore case) in log_file file. head prints first 10 lines of a file. $head -n 20 file_name prints 20 lines of a file_name. $head -17 file_name2...

Basic linux commands

Basic linux commands

Here are some useful commands in linux   Command Possible Keys Action touch create file pwd print working directory ls -l (more info) -la (hidden included) list files echo mkdir make directory cd change directory rm -r  (recursively) remove rmdir remove directory...