#15 LNK2019 errors when compiling libVISCA in VS2012

[David Andes]

When compiling libvisca.h and libvisca.c from 1.1.0 to make a static library in VS2012, I receive the following errors:

1>libvisca.obj : error LNK2019: unresolved external symbol __VISCA_write_packet_data referenced in function _VISCA_get_camera_info
1>libvisca.obj : error LNK2019: unresolved external symbol __VISCA_send_packet referenced in function _VISCA_clear
1>libvisca.obj : error LNK2019: unresolved external symbol __VISCA_get_packet referenced in function __VISCA_get_reply

In reviewing the source for libvisca.c, it appears the functions VISCA_write_packetdata, VISCA_send_packet and VISCA_get_packet are each undefined.

Am I missing something?

[Damien Douxchamps]

Hi,

I'm not exactly knowledgeable in windows stuff, but here's a few pointers that may help.
No function is called __VISCA_write_packet (same for the two other undefined ones). But _VISCA_write_packet (single underscore) and friends are defined in libvisca_win32.c. I assume the extra underscore is something about the windows compiler, so if the 3 functions are not found it's possible that the file libvisca_win32.c is not compiled properly?

Damien

[David Andes]

Oh my goodness. I am so embarassed to have missed that! I guess that's what I get for coding while NOT under the influence of caffeine!

Please close the ticket as Solved: User is an idiot.

[Damien Douxchamps]

:-)

[Rupesh]

Dear Sir,
I am using PIC MICROCONTROLLER

In this function I can't understand WriteFile function,because of this
function your code in not working in my compiler.

uint32_t
_VISCA_write_packet_data(VISCAInterface_t iface, VISCACamera_t camera,
VISCAPacket_t packet)
{
DWORD iBytesWritten;

WriteFile(iface->port_fd, packet->bytes, packet->length,
&iBytesWritten, NULL);
if ( iBytesWritten < packet->length )
return VISCA_FAILURE;
else
return VISCA_SUCCESS;
}
2nd doubt In this function I can't understand ReadFile *function,because
of this function your code in not working in my compiler.

uint32_t
_VISCA_get_packet(VISCAInterface_t *iface)
{
int pos=0;
BOOL rc;
DWORD iBytesRead;

// wait for message
rc=ReadFile(iface->port_fd, iface->ibuf, 1, &iBytesRead, NULL);
if ( !rc || iBytesRead==0 )
{
// Obtain the error code
//m_lLastError = ::GetLastError();
_RPTF0(_CRT_WARN,"ReadFile failed.\n");
return VISCA_FAILURE;
}
while (iface->ibuf[pos]!=VISCA_TERMINATOR) {
if ( ++pos >= VISCA_INPUT_BUFFER_SIZE )
{
// Obtain the error code
//m_lLastError = ::GetLastError();
_RPTF0(_CRT_WARN,"illegal reply packet.\n");
return VISCA_FAILURE;
}
rc=ReadFile(iface->port_fd, iface->ibuf + pos, 1, &iBytesRead, NULL);
if ( !rc || iBytesRead==0 )
{
// Obtain the error code
//m_lLastError = ::GetLastError();
_RPTF0(_CRT_WARN,"ReadFile failed.\n");
return VISCA_FAILURE;
}
}
iface->bytes=pos+1;

return VISCA_SUCCESS;
}
rest of thing are understandable

Please give response joshirupesh1989@gmail.com