Messages in this thread |  | | From | <> | Subject | Linux Kernel Message Queue Implementation | Date | Tue, Feb 18, 2003 at 19:47:52 IST (GMT+0530) |
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[1] msgsnd (int, struct msgbuf *, int, int) INTERFACE ERROR !!
[2] msgsnd() has "struct msgbuf*" as its 2nd parameter. When I tried to write an application which uses message queues for IPC i declared my message queue buffer as -
struct my_msgq_buf { long mtype; char *name; double amount; };
I allocated the memory of name dynamically using "malloc" and wrote into the message Queue using msgsnd. And the msgsnd returns successfully. When I do an msgrcv with the above structure type, I always recieve NULL values in my structure buffer !!
But, When I use the structure as declared below -
struct my_msgq_buf { long mtype; char name[30]; double amount; };
Every thing interstingly seems to be working fine.! The interface for msgsnd and msgrcv should have "void *" pointers rather than having a "struct msgbuf *" as parameters.
[3] Kernel [4] 2.4.7-10 [5] [6] [7] i586. Intel Pentium 166 MHz MMX. [8]
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