C / c++动态链接库过载

In my porject, I need to modify some functions of the glibc source code. I only need to modify part of the pthread. For example, I modified multithreaded related functions such as pthread_create.c or pthread_mutex_lock.c in the source code. Then, when my concrete program is running,I want to specify it to use the modified functions when it needs to using these functions ,and it won't affect other functions.Also,I do not want to specify an entire version of glibc when program is running. I need to ask for your help is there any good solution for this problem? Thanks!! DingIn my porject, I need to modify some functions