MYSQL : Portage de vieux code en C … misère.

Quelle misère ce portage sur une Fédora 14 :

# make
…
/usr/bin/ld: cannot find -lmysqlclient
 
# ldconfig -v | grep "mysql"
/usr/lib/mysql:
        libmysqlclient.so.16 -> libmysqlclient.so.16.0.0
        libmysqlclient_r.so.16 -> libmysqlclient_r.so.16.0.0
 
# rpm -qa | grep mysql
mysql-devel-5.1.58-1.fc14.i686
mysql-5.1.58-1.fc14.i686
mysql-libs-5.1.58-1.fc14.i686
 
# ld -lmysqlclient --verbose
GNU ld version 2.20.51.0.7-5.fc14 20100318
  Supported emulations:
   elf_i386
   i386linux
   elf_x86_64
   elf_l1om
using internal linker script:
==================================================
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==================================================
attempt to open /usr/i686-redhat-linux/lib/libmysqlclient.so failed
attempt to open /usr/i686-redhat-linux/lib/libmysqlclient.a failed
attempt to open /usr/local/lib/libmysqlclient.so failed
attempt to open /usr/local/lib/libmysqlclient.a failed
attempt to open /lib/libmysqlclient.so failed
attempt to open /lib/libmysqlclient.a failed
attempt to open /usr/lib/libmysqlclient.so failed
attempt to open /usr/lib/libmysqlclient.a failed
 
# locate /libmysqlclient.so
/usr/lib/mysql/libmysqlclient.so
/usr/lib/mysql/libmysqlclient.so.16
/usr/lib/mysql/libmysqlclient.so.16.0.0
 
# ln -s /usr/lib/mysql/libmysqlclient.so /lib/libmysqlclient.so
 
# make
: undefined reference to `mysql_connect'
 

Ensuite il a fallu changer les fonctions mysql_connect par mysql_real_connect :

mysql_real_connect(MYSQL *mysql, const char *host, const char *user, const char *passwd, const char *db, unsigned int port, const char *unix_socket, unsigned long client_flag);

Il faut retenir que le ‘ld’ permet de voir où doivent être les librairies.

Frédéric.