fq - a dynamic ffi for kdb+ 3.1

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Hi guys,Before I post this to the k4 list, I’d appreciate it if anyone wouldlike to try this out: http://www.ivorykite.com/fq/from that page: . load any shared object (.so) or .dll q)c:.fq.dlolibc.so.6 . load any functions or variables from a library q)fwrite:.fq.dlf[c;fwrite] q)stdout:.fq.dls[c;`stdout] . call any function in q (providing a call signature) q).fq.call[fwrite;“iCiiz”;(“ho\n”;3i;1i;stdout)]ThanksJack.

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how is it different from ffiq?

http://code.kx.com/wsvn/code/contrib/serpent.speak/trunk/ffiq/README

is it possible to call C functions taking struct/* as parameters?

thanks,
Ye

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> how is it different from ffiq?i plan to support it…> is it possible to call C functions taking struct/* as parameters?..such as adding support for struct parametersta, jack.

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support will be provided to define libc function prototypes like connect()
support for struct parameters will include .q files defining the structs used in functions like connect()

struct sockaddr_in server;
connect (sock, (struct sockaddr *) &server, sizeof server);

where server is a:? struct sockaddr_in
? {
? ? sa_family_t sin_family;
? ? in_port_t sin_port;
? ? struct in_addr sin_addr;
? ? unsigned char sin_zero[sizeof (struct sockaddr) -
? ? ? (sizeof (unsigned short int)) -
? ? ? sizeof (in_port_t) -
? ? ? sizeof (struct in_addr)];
? };

not a simple problem - but there are tools that will generate descriptions of structs - but will need to be done for each platform.

ta, jack

5

Sounds great, that’ll make it very useful.
– you can almost call any c library.

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Hi Ye,Yes, you can call any function in any shared object.I’ll add support for passing struct* to functions in the next week or so.Thanks,Jack.On 19 July 2013 21:55, Ye Tian wrote:> Sounds great, that’ll make it very useful.> – you can almost call any c library.>> On Jul 19, 2013, at 1:27 AM, Jack Andrews wrote:>> support will be provided to define libc function prototypes like connect()> support for struct parameters will include .q files defining the structs> used in functions like connect()>> struct sockaddr_in server;> connect (sock, (struct sockaddr *) &server, sizeof server);>> where server is a: struct sockaddr_in> {> sa_family_t sin_family;> in_port_t sin_port;> struct in_addr sin_addr;> unsigned char sin_zero[sizeof (struct sockaddr) -> (sizeof (unsigned short int)) -> sizeof (in_port_t) -> sizeof (struct in_addr)];> };>> not a simple problem - but there are tools that will generate descriptions> of structs - but will need to be done for each platform.>> ta, jack>> –>

Submitted via Google Groups

7

On Thursday, July 18, 2013 11:22:14 PM UTC-4, Jack Andrews wrote:

Before I post this to the k4 list, I’d appreciate it if anyone would
like to try this out:
  http://www.ivorykite.com/fq/

How does it compare to ffiq?

http://code.kx.com/wsvn/code/contrib/serpent.speak/trunk/ffiq/README

 

8

On 25 July 2013 01:23, Sasha <alexander.belopolsky> wrote:
>> Before I post this to the k4 list, I’d appreciate it if anyone would
>> like to try this out:
>> http://www.ivorykite.com/fq/
>>
> How does it compare to ffiq?

i’m working on struct/union, function prototypes and macro values

eg: an HTTP client using .fq*

$"fq Copyright (C) 2013 Ivorykite."<br>.fq:(fq 2:(fq;1))
c:.fq.libc
h:c.gethostbyname “google.com”
dest:c.sockaddr_in 0
sockfd:c.socket[dest.sin_family:c.AF_INET;c.SOCK_STREAM;0]
dest.sin_port:c.htons 80
c.memcpy[dest.sin_addr;h.h_addr;h.h_length]
connect[sockfd;dest;c.sizeof dest]
send[sockfd;g:“GET / HTTP/1.0\n\n”;count g]
({buffer:999#0x0;0<0N!c.recv[sockfd;buffer;count buffer]}/)`

if you have a similar small example for me to work off, please
send it through to me.

ta, jack


*which is similar to:
int main(int c, char *v)
{ int sockfd, bytes_read;
struct sockaddr_in dest;
char buffer[999];
if ( c != 2 )
return fprintf(stderr,“usage: %s host\neg. %s google.com\n”,v,v);
if ( (sockfd = socket(AF_INET, SOCK_STREAM, 0)) < 0 )
EX(“socket”);
bzero(&dest, sizeof(dest));
dest.sin_family = AF_INET;
dest.sin_port = htons(80);
struct hostenth=gethostbyname(v[1]);
memcpy(&dest.sin_addr,h->h_addr,h->h_length);
if ( inet_addr(v[1], &dest.sin_addr.s_addr) == 0 )
EX(v[1]);
if ( connect(sockfd, (struct sockaddr)&dest, sizeof(dest)) != 0 )
EX(“connect”);
sprintf(buffer,“GET / HTTP/1.0\n\n”);
send(sockfd, buffer, strlen(buffer), 0);
do {
bzero(buffer, sizeof(buffer));
bytes_read = recv(sockfd, buffer, sizeof(buffer), 0);
if ( bytes_read > 0 )
printf(“%s”, buffer);
} while ( bytes_read > 0 );
return 0;
}

</alexander.belopolsky>