PHP装好pdo_informix扩展后连接informix数据提示异常：
#0 ...: PDO->__construct(‘informix:host=1...‘, ‘user‘, ‘passwd‘)
#1 ...: DbIfx->__construct()
#3 {main}
thrown in ...
Fatal error: Uncaught exception ‘PDOException‘ with message ‘SQLSTATE=HY000, SQLDriverConnect: -11005 [Informix][Informix ODBC Driver]Unspecified System Error = -11005.‘ ed System Error = -11005.‘ in /usr/share/nginx/html/hydee/db.ifx.php:31
解决方法： 输入以下环境变量:
export INFORMIXDIR=/opt/IBM/Informix_Client-SDK/ export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:$INFORMIXDIR/lib:$INFORMIXDIR/lib/cli:$INFORMIXDIR/lib/esql
原文：https://www.cnblogs.com/equation/p/12157366.html