Bashrc guidelines

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The file .bashrc, located in your home directory, is read-in and executed whenever a bash script or bash shell is started. The exception is for login shells, in which case .bash_profile is started. The default .bash_profile calls .bashrc so that many scinet users never need to edit .bash_profile (the main exception is setting the PS1 variable, which you need to do in .bash_profile).

This means in particular that the file .bashrc is read in

  • when you log in
  • when you run compute jobs
  • when you run certain commands (such as mpirun, and python-script-called bash scripts).
  • at the end of a job, when copying output and error files.

Guidelines

To avoid difficulties, you are advised to follow these guidelines in .bashrc and .bash_profile:

  • Sourcing /etc/bashrc in .bashrc is required for various things to work on Niagara!
  • Do not execute any commands that write to standard output, because that would breaks things like copying-out output files and scp. So for instance, no echo or module list.
  • Do not load any modules in your .bashrc or .bash_profile (or if you must, only very commonly-used modules).
  • If you're trying out different implementations or versions of a module (e.g. mpi), you should definitely not load them in your .bashrc or .bash_profile, but explicitly on the command line before compiling and once more explicitly in your job script.

Default .bashrc and .bash_profile on Niagara

The default startup scripts provided by SciNet for Niagara are as follows. Certain things - like sourcing ~/.bashrc in ~/.bash_profile and /etc/bashrc in ~/.bashrc are required for various Niagara routines to work!


.bashrc

if [ -f /etc/bashrc ]; then
    . /etc/bashrc
fi

function sbatch() { 
    command sbatch --export=NONE "$@"
}
export -f sbatch

alias passwd='echo "Please use the CCDB web portal to change passwords: https://ccdb.computecanada.ca"'

# Do not change the commands above! Customized functions and aliases can be entered below.

alias rm='rm -i'
alias cp='cp -i'
alias mv='mv -i'
alias chmod='chmod -v'
alias more='/usr/bin/less'
alias df='/usr/bin/df -a -tgpfs -trootfs -h'

.bash_profile

if [ -f ~/.bashrc ]; then
    . ~/.bashrc
fi

# Do not change or remove the above lines.
# Additional variables and path settings can be set below.

export PS1='\u@\h:\w\$ '