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The available built-in commands are:
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run (aliases: execute, system). (default)
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Execute a single command on the command line shell.

It can take the following qualifiers

**ui**
    output will not be captured, but will be shown on the screen
    immediately - this allows the user to
    interact with the command. This may be necessary when the command
    expects input from the user. For example the dos command "dir /p" 
    will pause after each screen, without **ui** qualifier the script
    would appear to hang (as the message to press any key would not be 
    displayed).

**nocheck**
    Do not check the return value. Default is to raise an
    exception if the return value is not 0 (success)

**echo**
    Output is echo'ed to the terminal window after the process
    has finished executing.

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dirname
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Return the directory (or parent directory for a directory) of the 
path passed in.

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filename    (aliases basename)
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Return the filename (or directory name for a directory) of the 
path passed in.

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abspath
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Return the absolute path of the file. 

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count 
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exists  (aliases exist)
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check if the path (file or directory) exists or not. 
If the path exists - then it returns true. 
example::

  # if there is machine specific configuration then load it
  - if exists <shell.computername>.bb:
      - include <shell.computername>.bb
    

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notexists  (aliases notexist)
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check if the path (file or directory) exists or not. 
If the path does not exist - then it returns true. This can be useful
if you want to raise an error becuase one or more files does not exist.

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escapenewlines  (aliases escape_newlines)
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\r and \n characters in the input will be replaced with \\r and \\n
respectively.


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replace
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Allows you to replace text in a string

Usage::

    replace text to search in {*text to find*} {*replace with*}

Example::

    # get the contents of the text file
    - ser serverlocation = http://code.google.com/p/betterbatch/
    - set mail_contents = {{{ type email_template.txt }}}
    
    # replace the text 'SERVERLOCATION' in the email templaet
    # with 'http://code.google.com/p/betterbatch/'
    - echo {{{replace <mail_contents> {*SERVERLOCATION*} {*<serverlocation>*} }}}


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add_tools_dir
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