# ACE_Get_Opt Class Reference

Iterator for parsing command-line arguments. More...

`#include <Get_Opt.h>`

Collaboration diagram for ACE_Get_Opt:

[legend]
List of all members.

## Public Types

enum | { REQUIRE_ORDER = 1, PERMUTE_ARGS = 2, RETURN_IN_ORDER = 3 }
| Mutually exclusive ordering values. More...
enum | OPTION_ARG_MODE { NO_ARG = 0, ARG_REQUIRED = 1, ARG_OPTIONAL = 2 }
| Mutually exclusive option argument mode used by long options. More...

## Public Member Functions

| ACE_Get_Opt (int argc, ACE_TCHAR **argv, const ACE_TCHAR *optstring=ACE_LIB_TEXT(""), int skip_args=1, int report_errors=0, int ordering=PERMUTE_ARGS, int long_only=0)
| ~ACE_Get_Opt (void)
| Default dtor.
int | operator() (void)
ACE_TCHAR * | opt_arg (void) const
int | opt_opt (void)
int & | opt_ind (void)
int | long_option (const ACE_TCHAR *name, OPTION_ARG_MODE has_arg=NO_ARG)
| Adds a long option with no corresponding short option.
int | long_option (const ACE_TCHAR *name, int short_option, OPTION_ARG_MODE has_arg=NO_ARG)
| Adds a long option with a corresponding short option.
const ACE_TCHAR * | long_option (void) const
int | argc (void) const
| The number of arguments in the internal `argv_`.
ACE_TCHAR ** | argv (void) const
| Accessor for the internal `argv_` pointer.
const ACE_TCHAR * | last_option (void) const
void | dump (void) const
| Dump the state of an object.
const ACE_TCHAR * | optstring (void) const

## Public Attributes

int | argc_
| Holds the argc count.
ACE_TCHAR ** | argv_
| Holds the argv pointer.
int | optind
| Index in `argv_` of the next element to be scanned.
int | opterr
ACE_TCHAR * | optarg

## Private Member Functions

int | nextchar_i (void)
| Updates nextchar_.
int | long_option_i (void)
| Handles long options.
int | short_option_i (void)
| Handles short options.
void | permute_args (void)
int | permute (void)
| Handles reordering <argv>-elements.
void | last_option (const ACE_TString &s)
| Set last_option.
| ACE_Get_Opt (const ACE_Get_Opt &)
ACE_Get_Opt & | operator= (const ACE_Get_Opt &)

## Private Attributes

ACE_TString * | optstring_
| Holds the option string.
int | long_only_
| Treat all options as long options.
int | has_colon_
ACE_TString * | last_option_
ACE_TCHAR * | nextchar_
int | optopt_
| Most recently matched short option character.
int | ordering_
| Keeps track of ordering mode (default <permute_args>).
int | nonopt_start_
int | nonopt_end_
ACE_Get_Opt_Long_Option * | long_option_
| Points to the long_option found on last call to <operator()>.
ACE_Array< ACE_Get_Opt_Long_Option * > | long_opts_
| Array of long options.
| ACE_ALLOC_HOOK_DECLARE
| Declare the dynamic allocation hooks.

## Detailed Description

Iterator for parsing command-line arguments.

This is a C++ wrapper for getopt(3c) and getopt_long(3c).

## Member Enumeration Documentation

anonymous enum

Mutually exclusive ordering values.

Enumeration values:

  REQUIRE_ORDER | REQUIRE_ORDER means that processing stops and `EOF` is returned as soon as a non-option argument is found. `opt_ind()` will return the index of the next argv element so the program can continue processing the rest of the argv elements.
  PERMUTE_ARGS | PERMUTE_ARGS means the argv elements are reordered dynamically (permuted) so that all options appear first. When the elements are permuted, the order of the options and the following arguments are maintained. When the last option has been processed, `EOF` is returned and `opt_ind()` returns the index into the next non-option element.
  RETURN_IN_ORDER | RETURN_IN_ORDER means each argv element is processed in the order is it seen. If the element is not recognized as an option, '1' is returned and `opt_arg()` refers to the argv element found.

enum ACE_Get_Opt::OPTION_ARG_MODE

Mutually exclusive option argument mode used by long options.

Enumeration values:

  NO_ARG | Doesn't take an argument.
  ARG_REQUIRED | Requires an argument, same as passing ":" after a short option character in optstring.
  ARG_OPTIONAL | Argument is optional, same as passing "::" after a short option character in optstring.

## Constructor & Destructor Documentation

ACE_BEGIN_VERSIONED_NAMESPACE_DECL ACE_Get_Opt::ACE_Get_Opt | ( | int | argc,
|  | ACE_TCHAR ** | argv,
|  | const ACE_TCHAR * | optstring = `ACE_LIB_TEXT("")`,
|  | int | skip_args = `1`,
|  | int | report_errors = `0`,
|  | int | ordering = `PERMUTE_ARGS`,
|  | int | long_only = `0`
| ) |

Constructor initializes the command line to be parsed. All information for parsing must be supplied to this constructor.

Parameters:

  | argc | The number of argv elements to parse.
  | argv | Command line tokens, such as would be passed to `main()`.

  optstring

  Nul-terminated string containing the legitimate short option characters. A single colon ":" following an option character means the option requires an argument. A double colon "::" following an option character means the argument is optional. The argument is taken from the rest of the current argv element, or from the following argv element (only valid for required arguments; optional arguments must always reside in the same argv element). The argument value, if any is returned by the `opt_arg()` method. optstring can be extended by adding long options with corresponding short options via the `long_option()` method. If the short option already appears in optstring, the argument characteristics must match, otherwise it is added. See `long_option()` for more information. If 'W', followed by a semi-colon ';' appears in optstring, then any time a 'W' appears on the command line, the following argument is treated as a long option. For example, if the command line contains "program -W foo", "foo" is treated as a long option, that is, as if "program --foo" had been passed. The following characters can appear in optstring before any option characters, with the described effect:
  - '+' changes the ordering to REQUIRE_ORDER.
  - '-' changes the ordering to RETURN_IN_ORDER.
  - ':' changes the return value from `operator()` and get_opt() from '?' to ':' when an option requires an argument but none is specified.

  | skip_args | Optional (default 1). The specified number of initial elements in argv are skipped before parsing begins. Thus, the default prevents argv[0] (usually the command name) from being parsed. argc includes all argv elements, including any skipped elements.
  | report_errors | Optional, if non-zero then parsing errors cause an error message to be displayed from the `operator()` method before it returns. The error message is suppressed if this argument is 0. This setting also controls whether or not an error message is displayed in `long_option()` encounters an error.

  ordering

  Optional (default is `PERMUTE_ARGS`); determines how the argv elements are processed. This argument is overridden by two factors:
  1. The `POSIXLY_CORRECT` environment variable. If this environment variable is set, the ordering is changed to `REQUIRE_ORDER`.
  2. Leading characters in optstring (see above). Any leading ordering characters override both the ordering argument and any effect of the `POSIXLY_CORRECT` environment variable.

  | long_only | Optional. If non-zero, then long options can be specified using a single '-' on the command line. If the token is not a long option, it is processed as usual, that is, as a short option or set of short options.

Multiple short options can be combined as long as only the last one can takes an argument. For example, if optstring is defined as `"abc:"` or `"abc::"` then the command line "program -abcxxx" short options a, b, and c are found with "xxx" as the argument for c. However, if the command line is specified as "program -acb" only options a and c are found with "b" as the argument for c. Also, for options with optional arguments, that is, those followed by "::", the argument must be in the same argv element, so "program -abc xxx" will only find "xxx" as the argument for c if optstring is specified as `"abc:"` not `"abc::"`.

ACE_Get_Opt::~ACE_Get_Opt | ( | void |  | ) |

| Default dtor.

ACE_Get_Opt::ACE_Get_Opt | ( | const ACE_Get_Opt & |  | ) | `[private]`

## Member Function Documentation

ACE_INLINE int ACE_Get_Opt::argc | ( | void |  | ) | const

| The number of arguments in the internal `argv_`.

ACE_INLINE ACE_TCHAR ** ACE_Get_Opt::argv | ( | void |  | ) | const

| Accessor for the internal `argv_` pointer.

void ACE_Get_Opt::dump | ( | void |  | ) | const

| Dump the state of an object.

void ACE_Get_Opt::last_option | ( | const ACE_TString & | s | ) | `[private]`

| Set last_option.

const ACE_TCHAR * ACE_Get_Opt::last_option | ( | void |  | ) | const

| Accessor for the `last_option` that was processed. This allows applications to know if the found option was a short or long option, and is especially useful in cases where it was invalid and the caller wants to print out the invalid value.

const ACE_TCHAR * ACE_Get_Opt::long_option | ( | void |  | ) | const

| Returns the name of the long option found on the last call to `operator()` or 0 if none was found.

int ACE_Get_Opt::long_option | ( | const ACE_TCHAR * | name,
|  | int | short_option,
|  | OPTION_ARG_MODE | has_arg = `NO_ARG`
| ) |

Adds a long option with a corresponding short option.

Parameters:

  | name | The long option to add.
  | short_option | A character, the short option that corresponds to name.
  | has_arg | Defines the argument requirements for the new option. If the short option has already been supplied in the optstring, has_arg must match or an error is returned; otherwise, the new short option is added to the optstring.

Return values:

  | 0 | Success
  | -1 | The long option can not be added.

int ACE_Get_Opt::long_option | ( | const ACE_TCHAR * | name,
|  | OPTION_ARG_MODE | has_arg = `NO_ARG`
| ) |

Adds a long option with no corresponding short option.

If the name option is seen, `operator()` returns 0.

Parameters:

  | name | The long option to add.
  | has_arg | Defines the argument requirements for the new option.

Return values:

  | 0 | Success
  | -1 | The long option can not be added.

int ACE_Get_Opt::long_option_i | ( | void |  | ) | `[private]`

| Handles long options.

int ACE_Get_Opt::nextchar_i | ( | void |  | ) | `[private]`

| Updates nextchar_.

int ACE_Get_Opt::operator() | ( | void |  | ) |

Scan elements of argv (whose length is argc) for short option characters given in optstring or long options (with no short option equivalents).

If an element of argv starts with '-', and is not exactly "-" or "--", then it is a short option element. The characters of this element (aside from the initial '-') are option characters. If it starts with "--" followed by other characters it is treated as a long option. If `operator()` is called repeatedly, it returns each of the option characters from each of the option elements.

Returns:
  The parsed option character. The following characters have special significance.

Return values:

  | 0 | A long option was found
  | '\?' | Either an unknown option character was found, or the option is known but requires an argument, none was specified, and optstring did not contain a leading colon.
  | ':' | A known option character was found but it requires an argument and none was supplied, and the first character of optstring was a colon. `opt_opt()` indicates which option was specified.
  | '1' | `RETURN_IN_ORDER` was specified and a non-option argument was found.
  | EOF | No more option characters were found. `opt_ind()` will return the index in argv of the first argv element that is not an option. If `PERMUTE_ARGS` was specified, the argv elements have been permuted so that those that are not options now come last.

Note:
  The standards are unclear with respect to the conditions under which '?' and ':' are returned, so we scan the initial characters of optstring up unto the first short option character for '+', '-', and ':' in order to determine ordering and missing argument behavior.

ACE_Get_Opt& ACE_Get_Opt::operator= | ( | const ACE_Get_Opt & |  | ) | `[private]`

ACE_INLINE ACE_TCHAR * ACE_Get_Opt::opt_arg | ( | void |  | ) | const

| For communication from `operator()` to the caller. When `operator()` finds an option that takes an argument, the argument value is returned from this method, otherwise it returns 0.

ACE_INLINE int & ACE_Get_Opt::opt_ind | ( | void |  | ) |

Index in argv of the next element to be scanned. This is used for communication to and from the caller and for communication between successive calls to `operator()`. On entry to `operator()`, zero means this is the first call; initialize.

When `operator()` returns `EOF`, this is the index of the first of the non-option elements that the caller should itself scan.

Otherwise, `opt_ind()` communicates from one call to the next how much of argv has been scanned so far.

ACE_INLINE int ACE_Get_Opt::opt_opt | ( | void |  | ) |

| Returns the most recently matched option character. Especially useful when operator() returns ':' for an unspecified argument that's required, since this allows the caller to learn what option was specified without its required argument.

const ACE_TCHAR * ACE_Get_Opt::optstring | ( | void |  | ) | const

| Return the optstring. This is handy to verify that calls to long_option added short options as expected.

int ACE_Get_Opt::permute | ( | void |  | ) | `[private]`

| Handles reordering <argv>-elements.

void ACE_Get_Opt::permute_args | ( | void |  | ) | `[private]`

| If permuting args, this functions manages the nonopt_start_ and nonopt_end_ indexes and makes calls to permute to actually reorder the <argv>-elements.

int ACE_Get_Opt::short_option_i | ( | void |  | ) | `[private]`

| Handles short options.

## Member Data Documentation

ACE_Get_Opt::ACE_ALLOC_HOOK_DECLARE`[private]`

| Declare the dynamic allocation hooks.

int ACE_Get_Opt::argc_

Holds the argc count.

Deprecated:
  This is public for backwards compatibility only. It will be made private in a release of ACE past 5.3. Do not write code that relies on this member being public; use the `argc()` accessor method instead.

ACE_TCHAR** ACE_Get_Opt::argv_

Holds the argv pointer.

Deprecated:
  This is public for backwards compatibility only. It will be made private in a release of ACE past 5.3. Do not write code that relies on this member being public; use the `argv()` accessor method instead.

int ACE_Get_Opt::has_colon_`[private]`

| Keeps track of whether or not a colon was passed in <optstring>. This is used to determine the return value when required arguments are missing.

ACE_TString* ACE_Get_Opt::last_option_`[private]`

| This is the last option, short or long, that was processed. This is handy to have in cases where the option passed was invalid.

int ACE_Get_Opt::long_only_`[private]`

| Treat all options as long options.

ACE_Get_Opt_Long_Option* ACE_Get_Opt::long_option_`[private]`

| Points to the long_option found on last call to <operator()>.

ACE_Array<ACE_Get_Opt_Long_Option*> ACE_Get_Opt::long_opts_`[private]`

| Array of long options.

ACE_TCHAR* ACE_Get_Opt::nextchar_`[private]`

| The next char to be scanned in the option-element in which the last option character we returned was found. This allows us to pick up the scan where we left off * If this is zero, or a null string, it means resume the scan by advancing to the next <argv>-element.

int ACE_Get_Opt::nonopt_end_`[private]`

| Index of the <argv>-element following the last non-option element (only valid when permuting).

int ACE_Get_Opt::nonopt_start_`[private]`

| Index of the first non-option <argv>-element found (only valid when permuting).

ACE_TCHAR* ACE_Get_Opt::optarg

Deprecated:
  This is public for backwards compatibility only. It will be made private in a release of ACE past 5.3. Do not write code that relies on this member being public; use the `opt_arg()` accessor method instead.

int ACE_Get_Opt::opterr

Deprecated:
  This is public for backwards compatibility only. It will be made private in a release of ACE past 5.3. Do not write code that relies on this member being public; use the report_errors argument to this class's constructor instead.

int ACE_Get_Opt::optind

Index in `argv_` of the next element to be scanned.

Deprecated:
  This is public for backwards compatibility only. It will be made private in a release of ACE past 5.3. Do not write code that relies on this member being public; use the `opt_ind()` accessor method instead.

int ACE_Get_Opt::optopt_`[private]`

| Most recently matched short option character.

ACE_TString* ACE_Get_Opt::optstring_`[private]`

| Holds the option string.

int ACE_Get_Opt::ordering_`[private]`

| Keeps track of ordering mode (default <permute_args>).

The documentation for this class was generated from the following files:

- Get_Opt.h
- Get_Opt.cpp
- Get_Opt.inl