FORTRAN 延时函数

在子程序中需要用到一些延时功能，

1. 在vs编译器中直接调用  *call sleep(5),可以实现5s的延时
   

2. 在子程序中直接 *call sleep(5)，会出现‘’Problem during linking - Abaqus/Standard User Subroutines.   This error may be due to a mismatch in the Abaqus user subroutine arguments.   These arguments sometimes change from release to release, so user subroutines   used with a previous release of Abaqus may need to be adjusted.‘’，veryfication subroutine 是pass, 浪费了我好多时间，修改加上一句 *USE DFPORT，程序可以正确通过