diff --git a/README.md b/README.md index de60f6c..e283b17 100644 --- a/README.md +++ b/README.md @@ -763,8 +763,163 @@ e.g. replace all +##System +[[back to top](#handy-bash-oneliner-commands-for-tsv-file-editing)] +#####snapshot of the current processes + ps + +#####check graphics card + + lspci + +#####show IP address + + $ip add show +or + + ifconfig + +#####check system version + + cat /etc/*-release + +#####Linux Programmer's Manuel: hier- description of the filesystem hierarchy + + man hier + +#####list job + + jobs -l + +#####export PATH + + export PATH=$PATH:~/path/you/want + +#####make file execuable + + chmod +x filename +//you can now ./filename to execute it + +#####list screen + + screen -d -r + +#####echo screen name + + screen -ls + +#####check system (x86-64) + + uname -i + +#####surf the net + + links www.google.com + +#####add user, set passwd + + useradd username + passwd username + +#####edit variable for bash, (e.g. displaying the whole path) + + 1. joe ~/.bash_profile + 2. export PS1='\u@\h:\w\$' + //$PS1 is a variable that defines the makeup and style of the command prompt + 3. source ~/.bash_profile + +#####edit environment setting (e.g. alias) + + 1. joe ~/.bash_profile + 2. alias pd="pwd" //no more need to type that 'w'! + 3. source ~/.bash_profile + +#####list environment variables (e.g. PATH) + + $echo $PATH +//list of directories separated by a colon + +#####list all environment variables for current user + + $env + +#####show partition format + + lsblk + +#####soft link program to bin + + ln -s /path/to/program /home/usr/bin +//must be the whole path to the program + +#####show hexadecimal view of data + + hexdump -C filename.class + +#####jump to different node + + rsh node_name + +#####check port (active internet connection) + + netstat -tulpn + +#####find whick link to a file + + readlink filename + +#####check where a command link to (e.g. python) + + which python + +#####list total size of a directory + + du -hs . +or + + du -sb + +#####copy directory with permission setting + + cp -rp /path/to/directory + +#####store current directory + + pushd . $popd ;dirs -l + +#####show disk usage + + df -h +or + + du -h +or + + du -sk /var/log/* |sort -rn |head -10 + +#####show current runlevel + + runlevel + +#####switch runlevel + + init 3 or + telinit 3 + +#####permanently modify runlevel + + 1. edit /etc/init/rc-sysinit.conf + 2. env DEFAULT_RUNLEVEL=2 + +#####become root + + su + +#####become somebody + + su somebody