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Diffstat (limited to 'Documentation/technical/api-parse-options.txt')
-rw-r--r-- | Documentation/technical/api-parse-options.txt | 30 |
1 files changed, 29 insertions, 1 deletions
diff --git a/Documentation/technical/api-parse-options.txt b/Documentation/technical/api-parse-options.txt index 539863b1f9..e30c602f47 100644 --- a/Documentation/technical/api-parse-options.txt +++ b/Documentation/technical/api-parse-options.txt @@ -66,6 +66,12 @@ Steps to parse options non-option arguments in `argv[]`. `argc` is updated appropriately because of the assignment. + +You can also pass NULL instead of a usage array as fourth parameter of +parse_options(), to avoid displaying a help screen with usage info and +option list. This should only be done if necessary, e.g. to implement +a limited parser for only a subset of the options that needs to be run +before the full parser, which in turn shows the full help message. ++ Flags are the bitwise-or of: `PARSE_OPT_KEEP_DASHDASH`:: @@ -77,6 +83,28 @@ Flags are the bitwise-or of: Using this flag, processing is stopped at the first non-option argument. +`PARSE_OPT_KEEP_ARGV0`:: + Keep the first argument, which contains the program name. It's + removed from argv[] by default. + +`PARSE_OPT_KEEP_UNKNOWN`:: + Keep unknown arguments instead of erroring out. This doesn't + work for all combinations of arguments as users might expect + it to do. E.g. if the first argument in `--unknown --known` + takes a value (which we can't know), the second one is + mistakenly interpreted as a known option. Similarly, if + `PARSE_OPT_STOP_AT_NON_OPTION` is set, the second argument in + `--unknown value` will be mistakenly interpreted as a + non-option, not as a value belonging to the unknown option, + the parser early. That's why parse_options() errors out if + both options are set. + +`PARSE_OPT_NO_INTERNAL_HELP`:: + By default, parse_options() handles `-h`, `--help` and + `--help-all` internally, by showing a help screen. This option + turns it off and allows one to add custom handlers for these + options, or to just leave them unknown. + Data Structure -------------- @@ -170,7 +198,7 @@ The function must be defined in this form: The callback mechanism is as follows: -* Inside `funct`, the only interesting member of the structure +* Inside `func`, the only interesting member of the structure given by `opt` is the void pointer `opt->value`. `\*opt->value` will be the value that is saved into `var`, if you use `OPT_CALLBACK()`. |