Performance considerations

The following tips can help improve performance when using qsh.

• Do not use command substitutions in the value of the PS1 variable. This causes a new process to be started every time you press the <enter> key.

• Use input redirection instead of cat. For example, the following command:

  cat myfile | grep Hello
  

  can be replaced with this command:

  grep Hello < myfile
  

• Use built-in utilities whenever possible because they are run in the current process.

• Leave the SHELL variable unset. If a script file does not contain a "#!" on the first line, the script is run in the current activation of qsh.