I am trying to use VLFeat in my C code on Ubuntu 16.04.3. Following the official instructions, I created a test file:
extern "C"
{
#include <vlfeat/vl/svm.h>
}
int main (int argc, const char * argv[]) {
VL_PRINT ("Hello world!") ;
return 0;
}
From the command line, I can confirm that svm.h is in vlfeat/vl. I then try
gcc main.cpp
but get the error message
main.cpp:3:27: fatal error: vlfeat/vl/svm.h: No such file or directory
Any advice on how to correctly use VLFeat in C code? Thanks.
Related
The code is given below.
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
int main ( int argc, char *argv[] )
{
//FILE *fps;
char secret[512] =" ";
FILE *fps = fopen("/etc/comp2700/share/secret", "r");
if(fps == NULL)
{
printf("Secret file not found\n");
return 1;
}
fgets(secret, 512, fps);
printf("Secret: %s\n", secret);
fclose(fps);
return 0;
}
When I am trying to run this program it is repeatedly throwing the following error:
./attack1.c: line 4: syntax error near unexpected token `('
./attack1.c: line 4: `int main ( int argc, char *argv[] )'
You need to compile your source file with gcc as follows
gcc -o attack attack1.c
then run it with
./attack
You should read up on the difference between compiled versus interpreted languages.
There is a short video here explaining the difference.
You cannot run your C program from the command line as ./attack1.c. Normally the shell would refuse to execute the C source file because it should not have execute permission, but for some reason, on your system, it must have the x bits and is read by the default shell as a script.
Of course this fails because attack1.c contains C code, not a command file. Note that the #include lines are interpreted as comments by the shell and the error only occurs at line 4.
To run a C program, you must first compile it to produce an executable:
gcc -Wall -o attack1 attack1.c
And then run the executable if there were no compilation errors:
./attack1
You can combine these commands as
gcc -Wall -o attack1 attack1.c && ./attack1
First, you need to compile the attack.c code using the following command:
gcc attack.c
This will create one executable file a.out which you can run using the following command:
./a.out
Hope this helps you.
I have created wit_func.exe using Matlab. Now I am trying to run the program using C.
I have written the following code:
#include <stdio.h>
#include<stdlib.h>
int main(int argc, char **argv)
{
int r;
r=system("C:\\Users\\mails\\OneDrive\\Documents\\MATLAB\\Testing for the executable files\\wit_func.exe");
printf("%d",r);
getchar();
return 0;
}
I provided the path to that .exe file. I getting this following output:
'C:\Users\mails\OneDrive\Documents\MATLAB\Testing' is not recognized as an internal or external command,
operable program or batch file.
1
I also need to pass some integer arguments to this executable file. Can somebody help me run this program properly?
I'm trying to compile this code which call func from "libcfmapi.so" to decrypt "cfg" file
#include <stdlib.h>
#include <stdio.h>
int restorebackup(const char *tmp_cfg_name,const char *xml_cfg_name);
int ATP_CFM_ExtCustomImportEncryptedUserCfgFile(const char *tmp_cfg_name);
int main(int argc, char **argv)
{
int ret;
if(argc < 3)
{
printf("specify temp config file name.\n");
exit(1);
}
ret=restorebackup(argv[1],argv[2]);
return ret;
}
int restorebackup(const char *tmp_cfg_name,const char *xml_cfg_name)
{
int ret=0;
//ret = ATP_CFM_ExtDigVerifyFile(tmp_cfg_name,tmp_cfg_name);
if(ret != 0)
{
printf("Verify File failed.\n");
return ret;
}
ret = ATP_CFM_ExtCustomImportEncryptedUserCfgFile(tmp_cfg_name);
return ret;
}
but got error regarding func type declare
root#kali:~/debian-qemu# gcc h.c -o demo
/tmp/ccVbt5NT.o: In function `restorebackup':
h.c:(.text+0x8c): undefined reference to `ATP_CFM_ExtCustomImportEncryptedUserCfgFile'
collect2: error: ld returned 1 exit status
any help appreciated
The reason you're getting this error is because you're not linking against the required library, libcfmapi.so.
This is not a library you would expect to find in your Debian system as it is unique to the BT device you're trying to hack.
In short - get the lib from your device, cross compile to the device architecture against the lib you extracted from the device and you should be fine.
More information based on Ishay Peled answer:
readelf -s <pulled library> | grep ATP_CFM_ExtCustomImportEncryptedUserCfgFile
I suspect the problem isn't that function you call doesn't exist but rather there are no functions being displayed it is most likely empty just like nm result:
nm: libcfmapi.so: no symbols
do the command without piping to grep, my bet is your output is:
readelf -s libcfmapi.so
Dynamic symbol information is not available for displaying symbols.
If someone knows the way of getting the headers from the file, i believe then you can find your function you require then link and run (i too am trying to use libcfmapi.so, but lack the programming/reversing knowledge required).
when using a library, then must:
include that library in the link statement via
-l cfmapi
include the header file for that library in the source code:
#include <cfmapi.h>
This question already has answers here:
Cuda C - Linker error - undefined reference
(2 answers)
Closed 7 years ago.
I'm new to CUDA programming hence running into issues with compiling/ linking files. I'm trying to compile .c and .cu files.
Here are the files:
p3.c:
#include <stdlib.h>
#include <stdio.h>
extern void load_scheduler(int k, int j);
int blocks, threads;
int main(int argc, char* argv[])
{
if (argc > 1)
{
blocks = atoi(argv[1]);
threads = atoi(argv[2]);
}
else
exit(1);
load_scheduler(blocks, threads);
}
And scheduler.cu file:
#include <stdlib.h>
#include <stdio.h>
__global__ void sched_func()
{
int j = 6*5*threadIdx.x;
printf("%d\n",j);
}
void load_scheduler(int b, int n)
{
sched_func<<< b,n >>>();
}
I compile these two files using nvcc -c scheduler.cu p3.c and it seems fine
However, when I try to link these two files using nvcc -o cuda_proj scheduler.o p3.o, I get an error:
p3.o: In function `main':
p3.c:(.text+0x58): undefined reference to `load_scheduler'
collect2: ld returned 1 exit status
I may not be using the right steps to get this working, so if there's any other way I should try out, suggestions are welcome. I am also new to making Makefiles so want to stick to using nvcc commands on terminal.
Just added : extern "c" before load_scheduler definition. NVCC could not recognize the function definition as it belonged to .cu file, therefore the error.
extern "C"
void load_scheduler(int b, int n)
{
sched_func<<< b,n >>>();
}
I know splint is to issue warning messages about problems in C programs.
I installed it on my Ubuntu using 'sudo apt-get install splint'.
How do I use it on a C program or programs?
If you create the following C program in a file called test.c you can then use splint to perform a static analysis on the source to find possible problems.
The source code to put into the file test.c:
#include <stdio.h>
int main(int argc, char *argv[])
{
int a = 100;
int b[8];
printf("Hello c\n");
b[8] = 100; // error
return 0;
}
The command line used to run splint against the C source file to check for problems.
$ splint test.c +bounds -paramuse -varuse