Template Objects
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Template objects following methods:
`reset()'
Restore a pipeline template to its initial state.
`clone()'
Return a new, equivalent, pipeline template.
`debug(flag)'
If FLAG is true, turn debugging on. Otherwise, turn debugging off.
When debugging is on, commands to be executed are printed, and the
shell is given `set -x' command to be more verbose.
`append(cmd, kind)'
Append a new action at the end. The CMD variable must be a valid
bourne shell command. The KIND variable consists of two letters.
The first letter can be either of `'-'' (which means the command
reads its standard input), `'f'' (which means the commands reads a
given file on the command line) or `'.'' (which means the commands
reads no input, and hence must be first.)
Similarly, the second letter can be either of `'-'' (which means
the command writes to standard output), `'f'' (which means the
command writes a file on the command line) or `'.'' (which means
the command does not write anything, and hence must be last.)
`prepend(cmd, kind)'
Add a new action at the beginning. See `append()' for explanations
of the arguments.
`open(file, mode)'
Return a file-like object, open to FILE, but read from or written
to by the pipeline. Note that only one of `'r'', `'w'' may be
given.
`copy(infile, outfile)'
Copy INFILE to OUTFILE through the pipe.