What is the default maximum stack size for QNX in the main thread?

The stack size defined under OS Abstractor for QNX is as follows: #define OS_MIN_STACK_SIZE 16384 #define OS_MAX_STACK_SIZE 0xffffffff The above defines are in cross_os_def.h. It is recommended that you always use the default OS_MIN_STACK_SIZE which is defined across various target OS. For example, under Linux, this is directly mapped to pthread_stack_min define.