关于 Dev-C++ 中缺少 iconv.h 的问题

前言

在 C++ 中有个扩展库 ext，里面有一些黑科技（hash, splay, binomial_heap 等等），

在 Windows 环境中，我们运行 Dev-C++ 并在头文件写 #include<bits/extc++.h> 时，经常会收到 [Error] iconv.h: No such file or directory 的编译报错。

所以为了代替他，我们会写很多

#include<ext/pb_ds/hash_policy.hpp>

#include<ext/pb_ds/assoc_container.hpp>

诸如此类。这不失为一个解决方案，但是万能头显然更加方便快捷。

现在我们来试着解决这个问题。

Step 1

找到您电脑上头文件的存储位置。通常为 C:\Program Files (x86)\Dev-Cpp\MinGW64\lib\gcc\x86_64-w64-mingw32\4.9.2\include\c++。

如果找不到可以新建一个 cpp 文件，开头写上 #include<iostream> 然后 Ctrl+左键点一下就可以知道文件目录了。

Step 2

在此目录下新建一个 iconv.h 文件，把下列内容复制进去：

/* Copyright (C) 1999-2019 Free Software Foundation, Inc.

   This file is part of the GNU LIBICONV Library.

   The GNU LIBICONV Library is free software; you can redistribute it

   and/or modify it under the terms of the GNU Library General Public

   License as published by the Free Software Foundation; either version 2

   of the License, or (at your option) any later version.

   The GNU LIBICONV Library is distributed in the hope that it will be

   useful, but WITHOUT ANY WARRANTY; without even the implied warranty of

   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

   Library General Public License for more details.

   You should have received a copy of the GNU Library General Public

   License along with the GNU LIBICONV Library; see the file COPYING.LIB.

   If not, see <https://www.gnu.org/licenses/>.  */

/* When installed, this file is called "iconv.h". */

#ifndef _LIBICONV_H

#define _LIBICONV_H

#define _LIBICONV_VERSION 0x0110    /* version number: (major<<8) + minor */

extern __declspec (dllimport) int _libiconv_version; /* Likewise */

/* We would like to #include any system header file which could define

   iconv_t, 1. in order to eliminate the risk that the user gets compilation

   errors because some other system header file includes /usr/include/iconv.h

   which defines iconv_t or declares iconv after this file, 2. when compiling

   for LIBICONV_PLUG, we need the proper iconv_t type in order to produce

   binary compatible code.

   But gcc's #include_next is not portable. Thus, once libiconv's iconv.h

   has been installed in /usr/local/include, there is no way any more to

   include the original /usr/include/iconv.h. We simply have to get away

   without it.

   Ad 1. The risk that a system header file does

   #include "iconv.h"  or  #include_next "iconv.h"

   is small. They all do #include <iconv.h>.

   Ad 2. The iconv_t type is a pointer type in all cases I have seen. (It

   has to be a scalar type because (iconv_t)(-1) is a possible return value

   from iconv_open().) */

/* Define iconv_t ourselves. */

#undef iconv_t

#define iconv_t libiconv_t

typedef void* iconv_t;

/* Get size_t declaration.

   Get wchar_t declaration if it exists. */

#include <stddef.h>

/* Get errno declaration and values. */

#include <errno.h>

/* Some systems, like SunOS 4, don't have EILSEQ. Some systems, like BSD/OS,

   have EILSEQ in a different header.  On these systems, define EILSEQ

   ourselves. */

#ifndef EILSEQ

#define EILSEQ

#endif

#ifdef __cplusplus

extern "C" {

#endif

/* Allocates descriptor for code conversion from encoding ‘fromcode’ to

   encoding ‘tocode’. */

#ifndef LIBICONV_PLUG

#define iconv_open libiconv_open

#endif

extern iconv_t iconv_open (const char* tocode, const char* fromcode);

/* Converts, using conversion descriptor ‘cd’, at most ‘*inbytesleft’ bytes

   starting at ‘*inbuf’, writing at most ‘*outbytesleft’ bytes starting at

   ‘*outbuf’.

   Decrements ‘*inbytesleft’ and increments ‘*inbuf’ by the same amount.

   Decrements ‘*outbytesleft’ and increments ‘*outbuf’ by the same amount. */

#ifndef LIBICONV_PLUG

#define iconv libiconv

#endif

extern size_t iconv (iconv_t cd,  char* * inbuf, size_t *inbytesleft, char* * outbuf, size_t *outbytesleft);

/* Frees resources allocated for conversion descriptor ‘cd’. */

#ifndef LIBICONV_PLUG

#define iconv_close libiconv_close

#endif

extern int iconv_close (iconv_t cd);

#ifdef __cplusplus

}

#endif

#ifndef LIBICONV_PLUG

/* Nonstandard extensions. */

#if 1

#if 0

/* Tru64 with Desktop Toolkit C has a bug: <stdio.h> must be included before

   <wchar.h>.

   BSD/OS 4.0.1 has a bug: <stddef.h>, <stdio.h> and <time.h> must be

   included before <wchar.h>.  */

#include <stddef.h>

#include <stdio.h>

#include <time.h>

#endif

#include <wchar.h>

#endif

#ifdef __cplusplus

extern "C" {

#endif

/* A type that holds all memory needed by a conversion descriptor.

   A pointer to such an object can be used as an iconv_t. */

typedef struct {

  void* dummy1[28];

#if 1

  mbstate_t dummy2;

#endif

} iconv_allocation_t;

/* Allocates descriptor for code conversion from encoding ‘fromcode’ to

   encoding ‘tocode’ into preallocated memory. Returns an error indicator

   (0 or -1 with errno set). */

#define iconv_open_into libiconv_open_into

extern int iconv_open_into (const char* tocode, const char* fromcode,

                            iconv_allocation_t* resultp);

/* Control of attributes. */

#define iconvctl libiconvctl

extern int iconvctl (iconv_t cd, int request, void* argument);

/* Hook performed after every successful conversion of a Unicode character. */

typedef void (*iconv_unicode_char_hook) (unsigned int uc, void* data);

/* Hook performed after every successful conversion of a wide character. */

typedef void (*iconv_wide_char_hook) (wchar_t wc, void* data);

/* Set of hooks. */

struct iconv_hooks {

  iconv_unicode_char_hook uc_hook;

  iconv_wide_char_hook wc_hook;

  void* data;

};

/* Fallback function.  Invoked when a small number of bytes could not be

   converted to a Unicode character.  This function should process all

   bytes from inbuf and may produce replacement Unicode characters by calling

   the write_replacement callback repeatedly.  */

typedef void (*iconv_unicode_mb_to_uc_fallback)

             (const char* inbuf, size_t inbufsize,

              void (*write_replacement) (const unsigned int *buf, size_t buflen,

                                         void* callback_arg),

              void* callback_arg,

              void* data);

/* Fallback function.  Invoked when a Unicode character could not be converted

   to the target encoding.  This function should process the character and

   may produce replacement bytes (in the target encoding) by calling the

   write_replacement callback repeatedly.  */

typedef void (*iconv_unicode_uc_to_mb_fallback)

             (unsigned int code,

              void (*write_replacement) (const char *buf, size_t buflen,

                                         void* callback_arg),

              void* callback_arg,

              void* data);

#if 1

/* Fallback function.  Invoked when a number of bytes could not be converted to

   a wide character.  This function should process all bytes from inbuf and may

   produce replacement wide characters by calling the write_replacement

   callback repeatedly.  */

typedef void (*iconv_wchar_mb_to_wc_fallback)

             (const char* inbuf, size_t inbufsize,

              void (*write_replacement) (const wchar_t *buf, size_t buflen,

                                         void* callback_arg),

              void* callback_arg,

              void* data);

/* Fallback function.  Invoked when a wide character could not be converted to

   the target encoding.  This function should process the character and may

   produce replacement bytes (in the target encoding) by calling the

   write_replacement callback repeatedly.  */

typedef void (*iconv_wchar_wc_to_mb_fallback)

             (wchar_t code,

              void (*write_replacement) (const char *buf, size_t buflen,

                                         void* callback_arg),

              void* callback_arg,

              void* data);

#else

/* If the wchar_t type does not exist, these two fallback functions are never

   invoked.  Their argument list therefore does not matter.  */

typedef void (*iconv_wchar_mb_to_wc_fallback) ();

typedef void (*iconv_wchar_wc_to_mb_fallback) ();

#endif

/* Set of fallbacks. */

struct iconv_fallbacks {

  iconv_unicode_mb_to_uc_fallback mb_to_uc_fallback;

  iconv_unicode_uc_to_mb_fallback uc_to_mb_fallback;

  iconv_wchar_mb_to_wc_fallback mb_to_wc_fallback;

  iconv_wchar_wc_to_mb_fallback wc_to_mb_fallback;

  void* data;

};

/* Requests for iconvctl. */

#define ICONV_TRIVIALP            0  /* int *argument */

#define ICONV_GET_TRANSLITERATE   1  /* int *argument */

#define ICONV_SET_TRANSLITERATE   2  /* const int *argument */

#define ICONV_GET_DISCARD_ILSEQ   3  /* int *argument */

#define ICONV_SET_DISCARD_ILSEQ   4  /* const int *argument */

#define ICONV_SET_HOOKS           5  /* const struct iconv_hooks *argument */

#define ICONV_SET_FALLBACKS       6  /* const struct iconv_fallbacks *argument */

/* Listing of locale independent encodings. */

#define iconvlist libiconvlist

extern void iconvlist (int (*do_one) (unsigned int namescount,

                                      const char * const * names,

                                      void* data),

                       void* data);

/* Canonicalize an encoding name.

   The result is either a canonical encoding name, or name itself. */

extern const char * iconv_canonicalize (const char * name);

/* Support for relocatable packages.  */

/* Sets the original and the current installation prefix of the package.

   Relocation simply replaces a pathname starting with the original prefix

   by the corresponding pathname with the current prefix instead.  Both

   prefixes should be directory names without trailing slash (i.e. use ""

   instead of "/").  */

extern void libiconv_set_relocation_prefix (const char *orig_prefix,

                                            const char *curr_prefix);

#ifdef __cplusplus

}

#endif

#endif

#endif /* _LIBICONV_H */

Step 3

保存。再次编译时可以顺利通过。

巴特西

关于 Dev-C++ 中缺少 iconv.h 的问题

前言

Step 1

Step 2

Step 3

最新文章

热门文章