在一台处理网络支付的服务器迁移的时候，发现不能支付。
PHP环境：
PHP版本为5.3.3系统为Red Hat 4.1.2-54查看apache的错误日志，发现是加密文件中一个函数bcmul()报错：
代码如下:
解决办法：
使用如下命令: 代码如下:
PHP-bcmath
就安装好了。
如果出现下面这种情况：
代码如下:
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
* base: mirrors.yun-idc.com
* extras: mirrors.yun-idc.com
* rpmforge: ftp.riken.jp
* updates: mirrors.yun-idc.com
Setting up Install Process
Resolving Dependencies
--> Running transaction check
---> Package PHP-bcmath.x86_64 0:5.1.6-40.el5_9 set to be updated
--> Processing Dependency: PHP-common = 5.1.6-40.el5_9 for package: PHP-bcmath
--> Running transaction check
---> Package PHP-common.x86_64 0:5.1.6-40.el5_9 set to be updated
--> Processing Conflict: PHP53-common conflicts PHP-common
--> Finished Dependency Resolution
PHP53-common-5.3.3-13.el5_9.1.x86_64 from installed has depsolving problems
--> PHP53-common conflicts with PHP-common
Error: PHP53-common conflicts with PHP-common
You could try using --skip-broken to work around the problem
You could try running: package-cleanup --problems
package-cleanup --dupes
rpm -Va --nofiles --nodigest
Loading mirror speeds from cached hostfile
* base: mirrors.yun-idc.com
* extras: mirrors.yun-idc.com
* rpmforge: ftp.riken.jp
* updates: mirrors.yun-idc.com
Setting up Install Process
Resolving Dependencies
--> Running transaction check
---> Package PHP-bcmath.x86_64 0:5.1.6-40.el5_9 set to be updated
--> Processing Dependency: PHP-common = 5.1.6-40.el5_9 for package: PHP-bcmath
--> Running transaction check
---> Package PHP-common.x86_64 0:5.1.6-40.el5_9 set to be updated
--> Processing Conflict: PHP53-common conflicts PHP-common
--> Finished Dependency Resolution
PHP53-common-5.3.3-13.el5_9.1.x86_64 from installed has depsolving problems
--> PHP53-common conflicts with PHP-common
Error: PHP53-common conflicts with PHP-common
You could try using --skip-broken to work around the problem
You could try running: package-cleanup --problems
package-cleanup --dupes
rpm -Va --nofiles --nodigest
就需要使用yum update 之后再yum install PHP53-bcmath就好了
顺便了解了一下，bcmath这个函数是PHP数学扩展中的一个。可以使用 bcscale() 来设置全局默认的小数位数，具体用法如下：
代码如下:
string bcmul ( string $left_operand,string $right_operand [,int $scale ] )
例子：
代码如下:
PHP
echobcmul('1.34747474747','35',3);//47.161
echobcmul('2','4');//8
?>
echobcmul('1.34747474747','35',3);//47.161
echobcmul('2','4');//8
?>
代码如下:
