Flags for `argp_parse'
----------------------
The default behavior of `argp_parse' is designed to be convenient
for the most common case of parsing program command line argument. To
modify these defaults, the following flags may be or'd together in the
FLAGS argument to `argp_parse':
`ARGP_PARSE_ARGV0'
Don't ignore the first element of the ARGV argument to
`argp_parse'. Unless `ARGP_NO_ERRS' is set, the first element of
the argument vector is skipped for option parsing purposes, as it
corresponds to the program name in a command line.
`ARGP_NO_ERRS'
Don't print error messages for unknown options to `stderr'; unless
this flag is set, `ARGP_PARSE_ARGV0' is ignored, as `argv[0]' is
used as the program name in the error messages. This flag implies
`ARGP_NO_EXIT'. This is based on the assumption that silent
exiting upon errors is bad behavior.
`ARGP_NO_ARGS'
Don't parse any non-option args. Normally these are parsed by
calling the parse functions with a key of `ARGP_KEY_ARG', the
actual argument being the value. This flag needn't normally be
set, as the default behavior is to stop parsing as soon as an
argument fails to be parsed. Note:Argp Parser Functions.
`ARGP_IN_ORDER'
Parse options and arguments in the same order they occur on the
command line. Normally they're rearranged so that all options
come first.
`ARGP_NO_HELP'
Don't provide the standard long option `--help', which ordinarily
causes usage and option help information to be output to `stdout'
and `exit (0)'.
`ARGP_NO_EXIT'
Don't exit on errors, although they may still result in error
messages.
`ARGP_LONG_ONLY'
Use the gnu getopt `long-only' rules for parsing arguments. This
allows long-options to be recognized with only a single `-' (i.e.
`-help'). This results in a less useful interface, and its use is
discouraged as it conflicts with the way most GNU programs work as
well as the GNU coding standards.
`ARGP_SILENT'
Turns off any message-printing/exiting options, specifically
`ARGP_NO_EXIT', `ARGP_NO_ERRS', and `ARGP_NO_HELP'.