Command language

This detailed reference information is a good starting point if you are writing shell scripts or are an experienced user of shells.

qsh is a program that do the following tasks:

  • reads input from either a file or a terminal
  • breaks the input into tokens
  • parses the input into simple and compound commands
  • performs various expansions on each command
  • performs redirection of input and output
  • runs the commands
  • optionally waits for the commands to complete

qsh implements a command language that has flow control constructs, variables, and functions. The interpretative language is common to both interactive and non-interactive use (shell scripts). So the same commands that are entered at an interactive command line can also be put in a file and the file can be run directly by qsh.

See the AIX® Information Center for more information about commands.