I am trying to compile a small .c file which uses OpenSSL includes, at first I had problems compiling but I solved it installing libssl-dev and that solved the include errors.
But now when I try to compile I get:
‘ssl_conn’ has no member named ‘encrypted’
‘ssl_conn’ has no member named ‘write_seq’
‘ssl_conn’ has no member named ‘read_seq’
The code for the lines of the error is:
ssl_conn* sslCon;
sslCon->encrypted = 0;
sslCon->write_seq = 0;
sslCon->read_seq = 0;
A friend told me it could be because the .c file was coded for an old version of OpenSSL, but I am not sure. Does someone knows what could be causing this and how to solve it?
ssl_conn is not part of the OpenSSL API and never was. I only found reference to it in some sample code exploiting OpenSSL, and it was defining it itself. Assuming you aren't trying to use that exploit code, my guess is there's an example floating around online from which you got the code you are trying to compile. So check your definition of ssl_conn and ensure it has the fields that are missing.
Related
I don't know if I can ask this question again,
There are many duplicates but none of the solutions actually worked for me
I'm using gcc version 4.6.1 (GCC)
And by trying to build I get
undefined reference to `fopen_s'
Please make your suggestions on how I can solve this issue :)
Note: I'm using Windows 7 / 64-bit
Thanks in advance.
Maybe you're not including the file its written in. Not sure where it is but it'd be something like "#include name.h", unless its a function you wrote yourself, in which case you'll need to create a .h file and include it at the top of both this file and the file you wrote that function in, like this " #include "name.h" "
I've added a new function wiringPiVersion() to wiringPi, but after I build and install the shared library, when I attempt to compile a small C program around it, I get:
wpi_ver.c:(.text+0xc): undefined reference to `wiringPiVersion'
However, when I include it in an XS based Perl module, all works well. I don't know enough about C to figure out what's going wrong here, and I've been searching for the better part of two hours trying different things to no avail.
Here's my small C program to test the new function:
#include <stdio.h>
#include <wiringPi.h>
int main (){
char * ver = wiringPiVersion();
printf("wiringPi version: %s\n", ver);
return 0;
}
Compilation that throws the error:
gcc -o ver wpi_ver.c -lwiringPi
The addition to wiringPi's header file:
extern char * wiringPiVersion(void);
The wiringPi's .c file addition:
#define WPI_VERSION "2.36"
char * wiringPiVersion(void){
return WPI_VERSION;
}
In my Perl module's XS file, I have:
char *
wiringPiVersion()
...and my Perl module's Makefile.PL
LIBS => ['-lwiringPi'],
...and after re-installing the Perl module, I can access the function without any issues in a test script.
I'm hoping this is something simple I'm overlooking which someone may be able to point out. My question is, how do I rectify this?
So it turned out that there were two .so files generated when I rebuilt wiringPi... one in the wiringPi's build directory way under my home directory, and the other in /usr/local/lib.
After a tip in comments, I added the library path explicitly:
gcc -o ver wpi_ver.c -L/usr/local/lib -lwiringPi
...and it all fell together and works as expected:
$ ./ver
wiringPi version: 2.36
Note: I have sent Gordon the patch in hopes it gets included in the next wiringPi cut.
Update: I received an email back from Gordon and he stated that currently, only the gpio application has the ability to report the version, so he advised that he's going to add something similar to my patch in a future release.
Although already solved, I added this answer to show what gave me the hint.
Error message "undefined reference" points to a linker error (cf. answer on SO), so its about checking if the correct library is drawn.
I have a project for college, where i need to use libjpeg (C language), to complete 2 codes the teacher gave to us. It's a about transforming a pic into ASCII symbols (like the ASCII draws, you know)
We have a code for reading a jpg and a code for writing a jpg.
The problem is i had to install the libjpeg, i THINK the installation went well but i'm not sure so i have 2 questions
How can i verify libjpeg is correctly installed ? i didn't link it to gcc so i have to use the option for saying to gcc where is jpeg-6b (the folder which contains ljpeg) so i tried this :
Typing "gcc -L/jpeg-6b" the folder is jpeg-6b and it's right on the location where i do the command. i only get an error message about the fact the input is empty (normal ok), i think if the lib was not correctly installed, i should get an error for saying me i can't use the libjpeg version, right ?
In the 2 codes i said the teacher gave to us, she puts #include <libjpeg> on the beginning of it. But i saw on the internet that people use #include <jpeglib.h>, but both of them DON'T work and i get a message telling me :
test.c:1:21: fatal error: jpeglib.h: no such file or directory
#include <jpeglib.h>
is my include bad? or is the libjpeg bad installed ? (i read the doc and i did ./configure then make like it's said)
Just as you add -L/jpeg-6b you need -I/jpeg-6b/path/to/jpeg/headers too. I would recommend a Makefile to automate this.
I am trying to port a program that uses GCD (Grand Central Dispatch) from OSX to Ubuntu 11.10. I installed libdispatch but I keep getting the following error:
undefined reference to dispatch_main()
The strange thing is that dispatch_main() is declared in a header file that I include and I call other functions declared in that header file and the compiler recognizes them. It is only dispatch_main() that it cannot see and if I call dispatch_main(2) it says that there are too many arguments, so I know the compiler can see the header.
I tried separating the compile and link steps (clang -c...) since that worked for an undefined reference error before, but it doesn't seem to do anything here...
Anybody have any suggestions? I'm pretty stumped on this one...
It sounds like you are missing the library from your link line. When you compile your program into an executable, add the library to the command. I am guessing it should look something like this:
clang x.c y.c z.c -ldispatch
I am working on a project which requires me to download and use this. Inside the downloaded folder, when extracted I am presented with three things:
A folder called "include"
A folder called "src"
A file called "Makefile"
After some research, I found out that I have to navigate to the directory which contains these files, and just type in the command make.
It seemed to install the library in my system. So I tried a sample bit of code which should use the library:
csp_conn_t * conn;
csp_packet_t * packet;
csp_socket_t * socket = csp_socket(0);
csp_bind(socket, PORT_4);
csp_listen(socket, MAX_CONNS_IN_Q);
while(1) {
conn = csp_accept(socket, TIMEOUT_MAX);
packet = csp_read(conn, TIMEOUT_NONE);
printf(“%S\r\n”, packet->data);
csp_buffer_free(packet);
csp_close(conn);
}
That's all that was given for the sample server end of the code. So I decided to add these to the top:
#include <csp.h>
#include <csp_buffer.h>
#include <csp_config.h>
#include <csp_endian.h>
#include <csp_interface.h>
#include <csp_platorm.h>
Thinking I was on the right track, I tried to compile the code with gcc, but I was given this error:
csptest_server.c:1: fatal error: csp.h: No such file or directory
compilation terminated.
I thought I may not have installed the library correctly after all, but to make sure, I found out I could check by running this command, and getting this result:
find /usr -iname csp.h
/usr/src/linux-headers-2.6.35-28-generic/include/config/snd/sb16/csp.h
/usr/src/linux-headers-2.6.35-22-generic/include/config/snd/sb16/csp.h
So it seems like the csp.h is installed, maybe I am referencing it incorrectly in the header include line? Any insight? Thanks a lot.
The make command is probably only building the library, but not installing it. You could try sudo make install. This is the "common" method, but I recommend you to check the library's documentation, if any.
The sudo command is only necessary if you have no permissions to write the system's include and library directories, which may be your case.
Another possibility (instead of installing the library) is telling GCC the location of the library's source code and generated binaries (by means of the -I and -L options of the gcc command.
That Makefile will not install anything, just translate the source into a binary format.
The csp.h in the Linux kernel has nothing to do with your project, it's just a naming collision, likely to happen with three letter names.
In your case, I would presume you need to add the include directory to the compilation flags for your server, like gcc -I/path/to/csp/include/csp csptest_server.c.
(Next, you'll run into linker errors because you'll also want to specify -L/path/to/csp -lcsp so that the linker can find the binary code to link to.)