Obtain a list of process scheduling policy and priority
Normally, you can read the file /proc/[pid]/sched and get the related information. But since I am using a simplified one, the sched file is not presented. And I need to figure out another way to get it. I finally found there is a C library, <sched.h>, to do that. You can find the following declarations in the library.
struct sched_param {
int sched_priority;
};
/* Set scheduling parameters for a process */
int sched_setparam(pid_t pid, const struct sched_param *param);
/* Retrieve scheduling parameters for a particular process */
int sched_getparam(pid_t pid, struct sched_param *param);
/* Set scheduling algorithm and/or parameters for a process */
int sched_setscheduler(pid_t pid, int policy, const struct sched_param *param);
/* Retrieve scheduling algorithm for a particular purpose */
int sched_getscheduler(pid_t pid);
In this case, we only need sched_getparam() to obtain scheduling priority and sched_getscheduler() to obtain scheduling policy.
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