使用哪个库？libmariadbclient还是libmysqlclient？

不知什么原因，我的libmysqlclient.a在我的CentOS 7中消失了。 然后我的程序出现链接器错误，说找不到libmysqlclient

然后我发现我的mysql-devel包不见了：

yum info mysql-devel
yum install mysql-devel

以下是答复：

Loaded plugins: fastestmirror
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Package MariaDB-devel-10.2.5-1.el7.centos.x86_64 already installed and latest version

所以我想也许我应该改用libmariadbclient，但是当我将我的程序链接到libmariadbclient时，它出现了链接错误：

/usr/lib64//libmariadbclient.a(openssl.c.o): In function `ma_tls_start':
(.text+0x191): undefined reference to `CRYPTO_num_locks'
/usr/lib64//libmariadbclient.a(openssl.c.o): In function `ma_tls_start':
(.text+0x1aa): undefined reference to `CRYPTO_THREADID_set_callback'
/usr/lib64//libmariadbclient.a(openssl.c.o): In function `ma_tls_start':
(.text+0x1b6): undefined reference to `CRYPTO_set_locking_callback'
/usr/lib64//libmariadbclient.a(openssl.c.o): In function `ma_tls_start':
(.text+0x1bb): undefined reference to `SSL_library_init'
/usr/lib64//libmariadbclient.a(openssl.c.o): In function `ma_tls_start':
(.text+0x1c7): undefined reference to `SSL_load_error_strings'
/usr/lib64//libmariadbclient.a(openssl.c.o): In function `ma_tls_start':
(.text+0x1cc): undefined reference to `OPENSSL_add_all_algorithms_noconf'
/usr/lib64//libmariadbclient.a(openssl.c.o): In function `ma_tls_end':
(.text+0x2b4): undefined reference to `CRYPTO_set_locking_callback'
/usr/lib64//libmariadbclient.a(openssl.c.o): In function `ma_tls_end':
(.text+0x2bb): undefined reference to `CRYPTO_set_id_callback'
/usr/lib64//libmariadbclient.a(openssl.c.o): In function `ma_tls_end':
(.text+0x2df): undefined reference to `CRYPTO_num_locks'
/usr/lib64//libmariadbclient.a(openssl.c.o): In function `ma_tls_end':
(.text+0x340): undefined reference to `EVP_cleanup'
/usr/lib64//libmariadbclient.a(openssl.c.o): In function `ma_tls_end':
(.text+0x345): undefined reference to `CRYPTO_cleanup_all_ex_data'
/usr/lib64//libmariadbclient.a(openssl.c.o): In function `ma_tls_end':
(.text+0x34a): undefined reference to `ERR_free_strings'
/usr/lib64//libmariadbclient.a(openssl.c.o): In function `ma_tls_end':
(.text+0x351): undefined reference to `CONF_modules_free'
/usr/lib64//libmariadbclient.a(openssl.c.o): In function `ma_tls_init':
(.text+0x3e1): undefined reference to `SSLv23_client_method'
/usr/lib64//libmariadbclient.a(openssl.c.o): In function `my_cb_threadid':
(.text+0x1e): undefined reference to `CRYPTO_THREADID_set_numeric'
/usr/lib64//libmariadbclient.a(ma_compress.c.o): In function `_mariadb_compress_alloc':
(.text+0x5d): undefined reference to `compress'
/usr/lib64//libmariadbclient.a(ma_compress.c.o): In function `_mariadb_uncompress':
(.text+0x191): undefined reference to `uncompress'
collect2: error: ld returned 1 exit status

我一直在使用libmysqlclient连接我的MariaDB 10.1，最近我一直在尝试从源代码构建它，但由于OpenSSL 1.1版本的问题而失败。在这里你可以看到我的另一篇文章：

所以我很困惑为什么mysqlclient.a消失了，我应该使用哪个库

有人能帮忙吗

---

谢谢

我在尝试使用“-lmariadbclient”编译程序时遇到了类似的问题（在apt获得更新后，-lmysqlclient停止工作）。 我使用的Makefile是：

g++ -std=c++11 *.cpp ../common/*.cpp ../common/*.c -o myprogram -I.. -ldl -Wstack-protector -fstack-protector-all -pthread -ggdb -lssl -lcrypto -lz -lmariadbclient -Wwrite-strings  -fPIC 

我了解到必须添加命令“-lssl-lcrypto-lz”来修复这些错误，但我将它们放在了错误的位置（在lmariadbclient之前）。当我在“-lmariadbclient”之后添加它们时，我终于能够编译我的程序：

g++ -std=c++11 *.cpp ../common/*.cpp ../common/*.c -o myprogram -I.. -ldl -Wstack-protector -fstack-protector-all -pthread -ggdb -lmariadbclient -Wwrite-strings -lssl -lcrypto -lz -fPIC 

2017年7月22日更新：

我最近尝试在新的LinuxMint18.2上编译我的程序。不幸的是，我遇到了同样的编译错误，我无法用旧方法修复它：

MariaDB版本：

 mysql --version
 mysql  Ver 15.1 Distrib 10.2.7-MariaDB, for debian-linux-gnu (x86_64) using readline 5.2

编译错误：

/usr/lib/gcc/x86_64-linux-gnu/5/../../../x86_64-linux-gnu/libmariadbclient.a(openssl.c.o): In function `ma_tls_start':
(.text+0x189): undefined reference to `CRYPTO_num_locks'
/usr/lib/gcc/x86_64-linux-gnu/5/../../../x86_64-linux-gnu/libmariadbclient.a(openssl.c.o): In function `ma_tls_start':
(.text+0x1a4): undefined reference to `CRYPTO_THREADID_set_callback'
/usr/lib/gcc/x86_64-linux-gnu/5/../../../x86_64-linux-gnu/libmariadbclient.a(openssl.c.o): In function `ma_tls_start':
(.text+0x1b0): undefined reference to `CRYPTO_set_locking_callback'
/usr/lib/gcc/x86_64-linux-gnu/5/../../../x86_64-linux-gnu/libmariadbclient.a(openssl.c.o): In function `ma_tls_start':
(.text+0x1b5): undefined reference to `SSL_library_init'
/usr/lib/gcc/x86_64-linux-gnu/5/../../../x86_64-linux-gnu/libmariadbclient.a(openssl.c.o): In function `ma_tls_start':
(.text+0x1c1): undefined reference to `SSL_load_error_strings'
/usr/lib/gcc/x86_64-linux-gnu/5/../../../x86_64-linux-gnu/libmariadbclient.a(openssl.c.o): In function `ma_tls_start':
(.text+0x1c6): undefined reference to `OPENSSL_add_all_algorithms_noconf'
/usr/lib/gcc/x86_64-linux-gnu/5/../../../x86_64-linux-gnu/libmariadbclient.a(openssl.c.o): In function `ma_tls_end':
(.text+0x2a4): undefined reference to `CRYPTO_set_locking_callback'
/usr/lib/gcc/x86_64-linux-gnu/5/../../../x86_64-linux-gnu/libmariadbclient.a(openssl.c.o): In function `ma_tls_end':
(.text+0x2ab): undefined reference to `CRYPTO_set_id_callback'
/usr/lib/gcc/x86_64-linux-gnu/5/../../../x86_64-linux-gnu/libmariadbclient.a(openssl.c.o): In function `ma_tls_end':
(.text+0x2cf): undefined reference to `CRYPTO_num_locks'
/usr/lib/gcc/x86_64-linux-gnu/5/../../../x86_64-linux-gnu/libmariadbclient.a(openssl.c.o): In function `ma_tls_end':
(.text+0x330): undefined reference to `EVP_cleanup'
/usr/lib/gcc/x86_64-linux-gnu/5/../../../x86_64-linux-gnu/libmariadbclient.a(openssl.c.o): In function `ma_tls_end':
(.text+0x335): undefined reference to `CRYPTO_cleanup_all_ex_data'
/usr/lib/gcc/x86_64-linux-gnu/5/../../../x86_64-linux-gnu/libmariadbclient.a(openssl.c.o): In function `ma_tls_end':
(.text+0x33a): undefined reference to `ERR_free_strings'
/usr/lib/gcc/x86_64-linux-gnu/5/../../../x86_64-linux-gnu/libmariadbclient.a(openssl.c.o): In function `ma_tls_end':
(.text+0x33f): undefined reference to `CONF_modules_free'
/usr/lib/gcc/x86_64-linux-gnu/5/../../../x86_64-linux-gnu/libmariadbclient.a(openssl.c.o): In function `ma_tls_init':
(.text+0x3c1): undefined reference to `SSLv23_client_method'
/usr/lib/gcc/x86_64-linux-gnu/5/../../../x86_64-linux-gnu/libmariadbclient.a(openssl.c.o): In function `my_cb_threadid':
(.text+0x1e): undefined reference to `CRYPTO_THREADID_set_numeric'

我通过将“-lmariadbclient”更改为“-lmariadb”来修复它。在那之后，我能够编译没有错误的程序。我不确定这个解决方案是否适用于所有人，但值得一试：）

我的最终生成文件是：

g++ -std=c++11 *.cpp ../common/*.cpp ../common/*.c -o myprogram -I.. -ldl -Wstack-protector -fstack-protector-all -pthread -ggdb -lmariadb -Wwrite-strings -lssl -lcrypto -lz -fPIC 

---

祝你好运

我试着把-lmariadbclient放在前面，但是仍然有那些链接错误？我想应该是：“libssl-dev”、“openssl-devel”和“libz-dev”。Mona，我无法安装/找到libssl-dev，但我肯定我安装了openssl-devel和libz-deval，奇怪的是，系统显示我安装了openssl-devel-1.0.1e-60.el7_3.1.x86_64，但我手动安装了1.1.0e，更新版本。我使用的是1.1.0e版本，我也希望如此。也许版本不匹配是问题所在？如何强制MariaDB使用更新的openssl版本？@kchkg我更新了我的答案。升级到LinuxMint18.2后，我无法编译我的程序。似乎将“-lmariadbclient”更改为“-lmariadb”修复了它！