man(1) Manual page archive

     INTRO(1)                                                 INTRO(1)

          intro - introduction to commands

          This section describes publicly accessible commands in
          alphabetic order.

          The name of a particular machine at the foot of the page
          means that the command is there and not necessarily
          elsewhere.  `Local' means the same, without being specific
          about where.

          Section (6) for computer games.
          Section (7) for databases.
          Section (8) for `hidden' commands for booting, maintenance,
          How to get started, in the Introduction.

          Upon termination each command returns two bytes of status,
          one supplied by the system giving the cause for termination,
          and (in the case of `normal' termination) one supplied by
          the program, see wait and exit(2). The former byte is 0 for
          normal termination, the latter is customarily 0 for success-
          ful execution, nonzero to indicate troubles such as erro-
          neous parameters, bad or inaccessible data, or other inabil-
          ity to cope with the task at hand.  It is called variously
          `exit code', `exit status' or `return code', and is
          described only where special conventions are involved.