write(stringwrites string of bytes to the file at the current file pointer write_byte(bytewrites single byte into memory at the current file pointer notes although unix and windows supply slightly different mmap(functionsthis module can be used in portable manner by relying on the optional access parameter that is common to both functions for examplemmap(fileno,length,access=access_writewill work on both unix and windows certain memory mapping may only work with length that' multiple of the system page sizewhich is contained in the constant mmap pagesize on unix svr systemsanonymous mapped memory can be obtained by calling mmap(on the file /dev/zeroopened with appropriate permissions on unix bsd systemsanonymous mapped memory can be obtained by calling mmap(with negative file descriptor and the flag mmap map_anon msvcrt the msvcrt module provides access to number of useful functions in the microsoft visual runtime library this module is available only on windows getch(reads keypress and returns the resulting character this call blocks if keypress is not available if the pressed key was special function keythe call returns '\ or '\xe and the next call returns the keycode this function doesn' echo characters to the consolenor can the function be used to read ctrl+ getwch(the same as getch(except that unicode character is returned getche(like getch(except that characters are echoed (if printablegetwche(the same as getche(except that unicode character is returned get_osfhandle(fdreturns the file handle for file descriptor fd raises ioerror if fd is not recognized heapmin(forces the internal python memory manager to return unused blocks to the operating system this works only on windows nt and raises ioerror on failure lib fl ff