Hi All,

Could I request for some help on some code?

I ran into an error with semaphores with some book code using Cygwin on 
Windows.

The code will throw an error with sem_post().

I compiled it with gcc -o memwriter memwriter.c -lrt -lpthread

$ ./memwriter
Shared memory address: 0x6fffffff0000 [0..511]
backing file: /dev/shm/shMemEx
semptr is address 0x7ffffcc18 with value 0
SEM_VALUE_MAX is 1147483648
sem_post: Invalid argument <--------------------------- ERROR


According to feedback, the above error does not turn up on Linux.

May I know if this is supposed to happen on Cygwin on Windows?

If not, how can I solve this?

I've also attached the code for reference.


Thank you.


Kind regards,

YEO Kai Wei