A memory-mapped region often requires its attributes to be queried or changed in some fashion. This section looks at four system calls designed for this purpose:
|mprotect(2)||Change the access of the indicated memory pages.|
|madvise(2)||Advise the UNIX kernel how you intend to use your memory region.|
|mincore(2)||Determine if pages of mapped memory are currently in memory.|
|msync(2)||Where modifications exist, indicate what regions of memory should be updated to the mapped files.|
A memory-mapped region, entirely or in part, may have its access protections changed by the mprotect(2) system call. Its function synopsis is as follows:
#include <sys/types.h> #include <sys/mman.h> int mprotect(const ...