STREAMS Message Block MSG64BIT Flag

Edit online

The STREAMS modules and drivers establish the 64-bit or 32-bit user process context by setting the message block flag (the b_flag field of msgb structure), MSG64BIT.

This flag is set by the streams head when it allocates a message to process a system call from a 64-bit process. This flag is set for the putmsg, putpmsg, and ioctl system calls; for the I_STR and I_STRFDINSERT commands; and for transparent ioctls.