Added long getopt docs; by Fred

1 files changed, 31 insertions, 7 deletions

diff --git a/Doc/lib/libgetopt.tex b/Doc/lib/libgetopt.tex
index 3f9592a..c626b3c 100644
--- a/Doc/lib/libgetopt.tex
+++ b/Doc/lib/libgetopt.tex
@@ -3,12 +3,13 @@
 \stmodindex{getopt}
 This module helps scripts to parse the command line arguments in
 \code{sys.argv}.
-It uses the same conventions as the \UNIX{}
+It supports the same conventions as the \UNIX{}
 \code{getopt()}
 function (including the special meanings of arguments of the form
-\samp{-} and \samp{--}).
+\samp{-} and \samp{--}).  Long options similar to those supported by
+GNU software may be used as well via an optional third argument.
 It defines the function
-\code{getopt.getopt(args, options)}
+\code{getopt.getopt(args, options [, long_options])}
 and the exception
 \code{getopt.error}.
 
@@ -22,6 +23,10 @@ script wants to recognize, with options that require an argument
 followed by a colon (i.e., the same format that \UNIX{}
 \code{getopt()}
 uses).
+The third option, if specified, is a list of strings with the names of
+the long options which should be supported.  The leading \code{'--'}
+characters should not be included in the option name.  Options which
+require an argument should be followed by an equal sign (\code{'='}).
 The return value consists of two elements: the first is a list of
 option-and-value pairs; the second is the list of program arguments
 left after the option list was stripped (this is a trailing slice of the
@@ -32,8 +37,10 @@ prefixed with a hyphen (e.g.,
 and the option argument as its second element, or an empty string if the
 option has no argument.
 The options occur in the list in the same order in which they were
-found, thus allowing multiple occurrences.
-Example:
+found, thus allowing multiple occurrences.  Long and short options may
+be mixed.
+
+An example using only \UNIX{} style options:
 
 \bcode\begin{verbatim}
 >>> import getopt, string
@@ -48,9 +55,26 @@ Example:
 >>> 
 \end{verbatim}\ecode
 
+Using long option names is equally easy:
+
+\bcode\begin{verbatim}
+>>> s = '--condition=foo --testing --output-file abc.def -x a1 a2'
+>>> args = string.split(s)
+>>> args
+['--condition=foo', '--testing', '--output-file', 'abc.def', '-x', 'a1', 'a2']
+>>> optlist, args = getopt.getopt(args, 'x', [
+...     'condition=', 'output-file=', 'testing'])
+>>> optlist
+[('--condition', 'foo'), ('--testing', ''), ('--output-file', 'abc.def'), ('-x', '')]
+>>> args
+['a1', 'a2']
+>>> 
+\end{verbatim}\ecode
+
 The exception
-\code{getopt.error = 'getopt error'}
+\code{getopt.error = 'getopt.error'}
 is raised when an unrecognized option is found in the argument list or
 when an option requiring an argument is given none.
 The argument to the exception is a string indicating the cause of the
-error.
+error.  For long options, an argument given to an option which does
+not require one will also cause this exception to be raised.