On 2008-03-24, Galchin Vasili wrote:

vigalchin@ubuntu:~/FTP/Haskell/unix-2.2.0.0$ runhaskell Setup.hs build Preprocessing library unix-2.2.0.0... MQueue.hsc: In function 'main':

MQueue.hsc:102:0: error: invalid application of 'sizeof' to incomplete type 'struct mq_attr'

MQueue.hsc:102:0: error: invalid application of 'sizeof' to incomplete type 'struct mq_attr'

MQueue.hsc:102:0: error: invalid application of 'sizeof' to incomplete type 'struct mq_attr' compiling dist/build/System/Posix/MQueue_hsc_make.c failed comma

This looks as if only a "struct mq_attr;" definition is found, which lets opaque types be defined in C -- only pointers to it may be allocated by the compiler, not the actual struct, nor can sizeof be taken. Does your system have both /usr/include/mqueue.h and /usr/include/bits/mqueue.h -- Aaron Denney -><-

Galchin Vasili wrote:

line #102 ...

allocaBytes (#const sizeof(struct mq_attr)) $ \ p_attrs -> do

definition of struct mq_attr on Linux ...

struct mq_attr { long int mq_flags; /* Message queue flags. */ long int mq_maxmsg; /* Maximum number of messages. */ long int mq_msgsize; /* Maximum message size. */ long int mq_curmsgs; /* Number of messages currently queued. */ long int __pad[4]; };

Did you #include the header file that defines this struct? Claude -- http://claudiusmaximus.goto10.org