CThreads

Let's dive into CThreads Interface aka POSIX Threads which isn't shipped natively with C, it's based on Unix :

https://www.ibm.com/docs/en/zos/2.4.0?topic=files-pthreadh-thread-interfaces

Resources for POSIX Threads of Unix :

https://www.ibm.com/docs/en/i/7.1?topic=ssw_ibm_i_71/apis/concept8.htm
https://www.geeksforgeeks.org/thread-functions-in-c-c/

Mutex -- Mutually Exclusive -- Synchronized -- Object :

https://www.ibm.com/docs/en/zos/2.3.0?topic=functions-pthread-mutex-init-initialize-mutex-object

struct timespec --used by the Mutex System of pthread.h in C method :

#include <bits/types/struct_timespec.h>
/* Wait until lock becomes available, or specified time passes. */
extern int pthread_mutex_timedlock (pthread_mutex_t *__restrict __mutex,
				    const struct timespec *__restrict__abstime);

struct timespec -- source from GNU :

/* NB: Include guard matches what <linux/time.h> uses.  */
#ifndef _STRUCT_TIMESPEC
#define _STRUCT_TIMESPEC 1

#include <bits/types.h>
#include <bits/endian.h>

/* POSIX.1b structure for a time value.  This is like a `struct timeval' but
   has nanoseconds instead of microseconds.  */
struct timespec
{
  __time_t tv_sec;		/* Seconds.  */
#if __WORDSIZE == 64 \
  || (defined __SYSCALL_WORDSIZE && __SYSCALL_WORDSIZE == 64) \
  || __TIMESIZE == 32
  __syscall_slong_t tv_nsec;	/* Nanoseconds.  */
#else
# if __BYTE_ORDER == __BIG_ENDIAN
  int: 32;           /* Padding.  */
  long int tv_nsec;  /* Nanoseconds.  */
# else
  long int tv_nsec;  /* Nanoseconds.  */
  int: 32;           /* Padding.  */
# endif
#endif
};

#endif

https://en.cppreference.com/w/c/chrono/timespec

To Build, use shell command/terminal :

┌─[twisted@parrot]─[~/GradleProjects/CThreads/build]
└──╼ $./compile.sh 
Compiling the project
Successfully Compiled

To run :

┌─[twisted@parrot]─[~/GradleProjects/CThreads/output]
└──╼ $./ThreadsTest.exec
Main Thread joined
Async 2 joined
139843706689280 Aysnc 2 Terminated
Thread 1
Async 1 joined
139843715081984 Aysnc 1 Terminated
139843698296576 (Thread 1) has been detached & terminated
Thread 2
139843698296576 (Thread 2) has been detached & terminated
mutex_initialized & property settled to NORMAL single lock mutually events
mutex object obtained by Event 1 -- Event 1 execution starts
mutex_locked to this Event 1, concurrent threads will wait until unlock occurs
mutex object obtained by Event 2 -- Event 2 execution starts
mutex_locked to this Event 2, concurrent threads will wait until unlock occurs

Tips : You can open the code on vscode, use c++ code completion, syntax highlighting.