User accounts on Vista have bash as the default login shell. If you are unfamiliar with bash or the Linux command line, we recommend working through the Shells topic of the Introduction to Linux roadmap in the Cornell Virtual Workshop. Other shells (such as sh, csh/tcsh, and zsh) are available for use on Vista; to switch to one of these as your default shell, you must create a ticket through the TACC Help or the TACC User Portal. Execute cat /etc/shells for a full list of available shells.

Customization

If you would like to make customizations to your shell, it is recommended that you do so within the .bashrc file, which is sourced by .profile by default. In this way you will get a consistent environment within your shell regardless of how it is launched (login, interactive shell, or script). If you would like to reset your shell back to the default setup at any time, simply execute /usr/local/startup_scripts/install_default_scripts. For more information about bash startup files, see TACC's Quick Start Guide.

Environment Variables

Your shell environment consists of:

  • environment variables and functions defined in system startup scripts;
  • user customizations added by account startup scripts; and
  • configurations performed when loading modules (to be covered in the Modules section).

If you are unfamiliar with environment variables or need a refresher, please see the Environment Variables section of the Introduction to Linux roadmap. The table below highlights some of the important environment variables to be aware of while working on Vista:

Environment Variables.
Variable Description
PATH Stores a list of directory paths to executables, which the shell searches when you issue a command
MANPATH Stores a list of directory paths the man command searches for man pages
LD_LIBRARY_PATH Stores a list of directory paths to libraries, which compilers, linkers, and dynamic loaders search
varies by package Package-specific environment variables (e.g., TACC_FAMILY_GROMACS)
varies by package Site environment variables for packages (e.g., TACC_NVIDIA_DIR)

A full list of environment variables and their current values within your shell can be viewed by executing the env command. Make sure to differentiate appropriately between a variable's name and its value; the latter is obtained by prepending $ to the name, e.g., $PATH.

Text Editors
Tip: Learn shell commands and editors!
Regardless of your research workflow, you'll need to become skillful in Linux basics—and a command-line text editor such as emacs, nano, gedit, or vi/vim—in order to use an HPC system like Vista properly.

If you could use a primer in this area, tutorials for the two more fully-featured text editors (Vim and Emacs) are provided in the Text Editors topic of the Introduction to Linux roadmap. There you will also find external links for nano and gedit. Gaining proficiency in one of these text editors is a good way to enhance your productivity on any Linux system, and hence can be a great asset when doing research on a leadership-class system such as Horizon.

 
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CVW material development is supported by NSF OAC awards 1854828, 2321040, 2323116 (UT Austin) and 2005506 (Indiana University)