如何解决这些libcurl链接错误？

Question

[Administrator@windows ~]$ g++ client.cpp -lcurl -o client.exe
C:\DOCUME~1\ADMINI~1\LOCALS~1\Temp\ccKXFUtC.o:client.cpp:(.text+0x23): undefined reference to `_imp__curl_global_init'
C:\DOCUME~1\ADMINI~1\LOCALS~1\Temp\ccKXFUtC.o:client.cpp:(.text+0x5f): undefined reference to `_imp__curl_formadd'
C:\DOCUME~1\ADMINI~1\LOCALS~1\Temp\ccKXFUtC.o:client.cpp:(.text+0x9b): undefined reference to `_imp__curl_formadd'
C:\DOCUME~1\ADMINI~1\LOCALS~1\Temp\ccKXFUtC.o:client.cpp:(.text+0xa2): undefined reference to `_imp__curl_easy_init'
C:\DOCUME~1\ADMINI~1\LOCALS~1\Temp\ccKXFUtC.o:client.cpp:(.text+0xc8): undefined reference to `_imp__curl_easy_setopt'
C:\DOCUME~1\ADMINI~1\LOCALS~1\Temp\ccKXFUtC.o:client.cpp:(.text+0xe4): undefined reference to `_imp__curl_easy_setopt'
C:\DOCUME~1\ADMINI~1\LOCALS~1\Temp\ccKXFUtC.o:client.cpp:(.text+0xf1): undefined reference to `_imp__curl_easy_perform'
C:\DOCUME~1\ADMINI~1\LOCALS~1\Temp\ccKXFUtC.o:client.cpp:(.text+0x101): undefined reference to `_imp__curl_easy_cleanup'
C:\DOCUME~1\ADMINI~1\LOCALS~1\Temp\ccKXFUtC.o:client.cpp:(.text+0x10e): undefined reference to `_imp__curl_formfree'
C:\DOCUME~1\ADMINI~1\LOCALS~1\Temp\ccKXFUtC.o:client.cpp:(.text+0x11b): undefined reference to `_imp__curl_slist_free_all'
collect2: ld returned 1 exit status

我在linux上没有这个问题,所以我不知道为什么会在windows上发生这种情况.我已经google了它,除了邮件列表档案与相同的问题和回复说"谷歌它"没有找到任何东西.

我正在使用mingw.当我构建libcurl时,我确实得到了一些链接器警告,但它们似乎与ssl相关,我不知道它是否是一个大问题,因为它构建没有错误.

*** Warning: linker path does not have real file for library -lssl.
*** I have the capability to make that library automatically link in when
*** you link to this library.  But I can only do this if you have a
*** shared version of the library, which you do not appear to have
*** because I did check the linker path looking for a file starting
*** with libssl and none of the candidates passed a file format test
*** using a file magic. Last file checked: /ssl/lib/libssl.a

*** Warning: linker path does not have real file for library -lcrypto.
*** I have the capability to make that library automatically link in when
*** you link to this library.  But I can only do this if you have a
*** shared version of the library, which you do not appear to have
*** because I did check the linker path looking for a file starting
*** with libcrypto and none of the candidates passed a file format test
*** using a file magic. Last file checked: /ssl/lib/libcrypto.a

*** Warning: linker path does not have real file for library -lz.
*** I have the capability to make that library automatically link in when
*** you link to this library.  But I can only do this if you have a
*** shared version of the library, which you do not appear to have
*** because I did check the linker path looking for a file starting
*** with libz and none of the candidates passed a file format test
*** using a file magic. Last file checked: /mingw/lib//libz.a
*** The inter-library dependencies that have been dropped here will be
*** automatically added whenever a program is linked with this library
*** or is declared to -dlopen it.

*** Since this library must not contain undefined symbols,
*** because either the platform does not support them or
*** it was explicitly requested with -no-undefined,
*** libtool will only create a static version of it.

Answer 1

通过添加选项,我能够避免这些卷曲链接Windows(mingw win32)上的错误-lcurl.dll.-DCURL_STATICLIB在我的情况下不需要.

我的构建在mingw/lib文件夹中有两个libcurl文件: libcurl.a and libcurl.dll.a

Answer 2

Libtool只构建了静态libcurl而不是动态库.您的标题正在寻找动态libcurl.它可能不是libcurl中的错,因为我可以在支持的头看到的代码__declspec(dllimport)和__declspec(dllexport)(这是一个好兆头包的作者知道什么是什么.

技术细节:请参阅有关libssh的答案.

解决方案:编译-DCURL_STATICLIB.