Bash tweaks

Unless noted otherwise, add these snippets to your ~/.bashrc on the login node. Bash runs that file whenever you start a new interactive shell; the tilde ~ stands for your home directory. Run source ~/.bashrc to apply changes to the current shell.

Keep a complete shell history

By default, Bash keeps only the last 500 commands and writes the history file when a shell exits, so with several open shells (or screen tabs) commands get lost. This keeps up to 99 999 commands and appends each one to the history file as soon as you press Enter:

shopt -s histappend
HISTSIZE=99999
HISTFILESIZE=99999
PROMPT_COMMAND="history -a${PROMPT_COMMAND:+; $PROMPT_COMMAND}"

The last line adds history -a to PROMPT_COMMAND instead of replacing what may already be there.

Fancier prompt

This prompt shows your username, the host name and the current directory in different colours:

PS1="\[\033[36m\]\u\[\033[m\]@\[\033[32m\]\h:\[\033[33;1m\]\w\[\033[m\]\$ "

Slurm shorthands

sacct_nice_format="jobid,User,jobname%22,partition,state,NNodes%5,NodeList,Start,End,Elapsed,UserCPU"
showmyjobs()  { sacct --user="$USER" --format="$sacct_nice_format" --starttime="$(date --date='-1 month' +%F)" "$@"; }
showalljobs() { sacct --allusers   --format="$sacct_nice_format" --starttime="$(date --date='-1 month' +%F)" "$@"; }
alias si='sinfo -R -o "%25N %8u %21H %10t %E"'

• showmyjobs: your jobs from the last month. Extra options are passed on to sacct, for example showmyjobs -X to show one line per job, without its steps.
• showalljobs: everyone's jobs from the last month.
• si: nodes that are down or drained, with the reason.

They are functions rather than aliases so that "the last month" is computed each time you run them, not once when the shell starts. See job history and troubleshooting for what the columns and job states mean.

Show the compiler's include directories

Print the directories gcc searches for header files (your directory with .h files should be among them):

alias showinclude='echo | gcc -E -Wp,-v -'

It shows the paths of the gcc that is active: the system GCC 8.5, or the one from a loaded foss module (see software modules).

Find your public IP address

Print the IP address your computer uses on the internet, for example when you're unsure because of NAT or a VPN. Run this on your own computer:

curl ifconfig.me