local sh = require "sh"sh.run(...)Runs the command ... with os.execute.
sh.read(...)Runs the command ... with io.popen. When sh.read succeeds, it
returns the content of stdout. Otherwise it returns the error identified
by io.popen.
sh.write(...)(data)Runs the command ... with io.popen and feeds stdin with data.
sh.write returns the same values returned by os.execute.
sh.pipe(...)(data)Runs the command ... with io.popen or pandoc.pipe and feeds
stdin with data. When sh.pipe succeeds, it returns the content of
stdout. Otherwise it returns the error identified by op.popen or
pandoc.pipe.
sh(...)sh can be called as a function. sh(...) is a shortcut to
sh.read(...).