diff --git a/libc/include/pthread.h b/libc/include/pthread.h
index 99515da..97f023d 100644
--- a/libc/include/pthread.h
+++ b/libc/include/pthread.h
@@ -80,6 +80,9 @@
 #define PTHREAD_EXPLICIT_SCHED 0
 #define PTHREAD_INHERIT_SCHED 1
 
+#define PTHREAD_PRIO_NONE 0
+#define PTHREAD_PRIO_INHERIT 1
+
 #define PTHREAD_PROCESS_PRIVATE 0
 #define PTHREAD_PROCESS_SHARED 1
 
@@ -145,9 +148,11 @@
 int pthread_mutexattr_destroy(pthread_mutexattr_t* __attr);
 int pthread_mutexattr_getpshared(const pthread_mutexattr_t* __attr, int* __shared);
 int pthread_mutexattr_gettype(const pthread_mutexattr_t* __attr, int* __type);
+int pthread_mutexattr_getprotocol(const pthread_mutexattr_t* __attr, int* __protocol) __INTRODUCED_IN(28);
 int pthread_mutexattr_init(pthread_mutexattr_t* __attr);
 int pthread_mutexattr_setpshared(pthread_mutexattr_t* __attr, int __shared);
 int pthread_mutexattr_settype(pthread_mutexattr_t* __attr, int __type);
+int pthread_mutexattr_setprotocol(pthread_mutexattr_t* __attr, int __protocol) __INTRODUCED_IN(28);
 
 int pthread_mutex_destroy(pthread_mutex_t* __mutex);
 int pthread_mutex_init(pthread_mutex_t* __mutex, const pthread_mutexattr_t* __attr);