I'm starting some work into manual programming of nodes in OPNET however I am having a few troubles. I'm getting some information from packets and storing them in variables and want to output this to the simulation console. When I add the line puts(bcast_info) I get the following error.
C:/Users/Andrew/op_models/traffic_source.pr.c(74) : warning C4047:
'function' : 'const char *' differs in levels of indirection from
'Objid' C:/Users/Andrew/op_models/traffic_source.pr.c(74) : warning
C4024: 'puts' : different types for formal and actual parameter 1
Prior to adding the line mentioned above, the simulation worked perfectly and I got the basic text output. This is my code so far.
static void route_pk(void)
{
Packet * pkptr;
Objid bcast_info;
FIN(route_pk());
pkptr = op_pk_get(op_intrpt_strm ());
bcast_info = op_pk_bcast_get (pkptr);
printf ("Hello! \n");
puts("Hello from puts");
puts(bcast_info);
op_pk_send (pkptr, 1);
FOUT;
}
I appreciate that OPNET is a variation on the C language with some of its own methods etc but any help on what the errors actually mean and potential fixes would be much appreciated. Please be aware that I have never worked with C / C++ or this OPNET language before.
Please don't use the print() function. Use the op_prg_odb_print_major() function.
Objid is a special data type in Modeler. You can't print it to screen.
Related
I just started developing for Windows Phone and I'm stuck with one piece of exisiting code I need to maintain. It's a macro from a logging lib that is used in many places of existing code.
This is the macro:
#define LOG_FORMAT_FUNCTION(fmtarg, firstvararg) __attribute__((__format__ (__printf__, fmtarg, firstvararg)))
And this is a method definition that fails to use the above macro with error "{ expected" (In German "Error: Es wurde ein '{' erwartet."):
void LogTrace_s(const char* category, const char* format, ...) LOG_FORMAT_FUNCTION(2, 3);
Can you help me get rid of the error? I'd also like to know what actually the macro does exactly.
Edit: After rading this here I now understand that this macro is good for error checking formatted strings. Now that I know, I need it even more. But I still have no clue how to translate this to MS C++.
Yes you CAN just omit it. Use
#if _MSVC_VER
#define LOG_FORMAT_FUNCTION(fmtarg, firstvararg)
#endif
It is annotating the function with extra information to help gcc give you better warnings. It does not change the behavior of the code in any way.
Ok, so I want to use gstreamer library.
1. Situation
I have some code:
#include <gst/gstpipeline.h>
#include <gst/gst.h>
...
GstElement* pipe = gst_pipeline_new("PipeName");
Where gst_pipeline_new is declared in gstpipeline.h:
GstElement* gst_pipeline_new (const gchar* name) G_GNUC_MALLOC;
where non obvious "things" :) are defined somewhere in the system:
typedef struct _GstElement GstElement; // gstelement.h
typedef char gchar; // gtypes.h
#define G_GNUC_MALLOC __attribute__((__malloc__)) // gmacros.h
2. Problem
Since I use make for building I have no errors during compilation and linking. Program itself runs OK as well. However...
In Eclipse IDE I have the following error:
Description Resource Path Location Type
Invalid arguments '
Candidates are:
_GstElement * gst_pipeline_new(const ? *)
' file.cc /path/to/file line 106 Semantic Error
I added all include directories which are specified in Makefile to eclipse project configuration (Project->Properties->C/C++ General->Paths and Symbols->Includes->C++). Of course it's a C++ project.
3. Question
How to get rid of that Eclipse error? I have no clue how to do this... And it drives me mad since now I use some legacy code and I have around 100 errors like this one.
So far I've tried:
casting either by reinterpret_cast<>() or C-like casting to const gchar*
adding typedef char gchar at the beginning of the file - before any other include!
including gtypes.h (gchar is defined there) - also before any other include
redeclaring `_GstElement gst_pipeline_new(const gchar* name)'
Nither of those helped...
To me it looks like Eclipse does not see the gchar type since it says that the candidate is _GstElement * gst_pipeline_new(const ? *) Where ? substitutes the real type. But I have no idea how to make (or event force :)) Eclipse to see it...
Most probably eclipse just doesn't know about your include paths (for this specific library) and complains about the unindexed types and declarations.
You can add them under 'Project->Properties->C++ General->Paths and Symbols'
If this doesn't help, you can also switch off semantic error checking (see Code Analysis), either in whole or for particular error types.
As g-maulik suggested, It seems that it was really an indexer problem. After increasing the indexer cache limits everything works fine.
Go to Window->Preferences->C/C++->Indexer tab cache limits and increase (might be machine dependent):
Index Database cache:
Limit relative to the maximum heap size: 15%
Absolute limit: 128 MB
Header file cache:
Absolute Limit: 128 MB
I have been using the allegro 5 libraries for developing a game in C++ for some time. Today I got some weird error:
I have a class called level. I have a header file called levelhandler.
Here's how it looks:
#pragma once
#include "level.h"
level level_1;
level *currentlevel;
void initialize_levels()
{
currentlevel = &level_1;
}
When I try to compile it gives me strange errors like:
error C2086: 'int level' redefinition
error C2143: syntax error : missing ; before 'level_1'
I remember that it could compile before, and I did use currentlevel->Player.X a lot of times, but now I have a lot of that and it gives errors like these:
error C2227: left of '->Player' must point to a class/struct/generic type
error C4430: missing type specifier - int assumed
header pasted from comment
#pragma once
#include "entity.h"
// some more includes
class level {
public:
enum Tileset { ... };
enum Tile { ... };
int tiles[200][200];
player Player;
level(void);
~level(void);
};
Such errors are hard to find as long as you look at the "Error List" pane. Select View/Output to show the "Output" view. The line after the error C2086 shows the original definition of level.
You fill find an
int level;
there as the C2086 tells you. If it's the line
level level_1;
of your fist example you will have to check the last header file include in your compilation unit. It might end with an int or it has a unbalanced #if clause.
To find the exact location start using a Short, Self Contained, Correct (Compilable), Example. This helps you to find the bug and saves time of other with their crystal balls.
Edit:
Another way to find the reason for this unexpected behavior is to see the preprocessor output. Set the Generate Preprocessed File option int the C/C++/Preprocessor project property page to With line numbers (/P) and look in the generated <sourcefile>.i
Check that that level.h file has included what you intended.
Ok, so I've been tinkering around with my project the weekend, and I finally found out what whas the problem that gave me so many weird compiler errors. It seems that I had a lot of cases where two header files were including each other, and the compiler really didn't like that, so I corrected that, and now I'm ok. Thank you all for helping me, and have a great day!
I'm currently porting an application from Fortran to C and need to output some variables to compare results. I'm very new to Fortran, and although i understand the code and have now ported several thousand lines, I'm a noob at writing Fortran code myself.
This code:
write(6,'(A,I3,A,E12.8,A,E12.8,A,E12.8,A,E12.8,A,E12.8)') 'iHyd:',
& ih,'; dzdr: ',dzdr,'; tauray:', tauRay,'; zRay: ',
& zray,'; ampRay: ',realpart(aray),'+j*',
& imagpart(aray),'; qRay: ',qray,'; width :',w
Compiles fine, but when run, the program exits with:
At line 296 of file calcpr.for (unit = 6, file = 'stdout')
Fortran runtime error: Expected INTEGER for item 15 in formatted transfer, got REAL
(A,I3,A,E12.8,A,E12.8,A,E12.8,A,E12.8,A,E12.8)
^
q0: 1432.3944878270595
nArrayR: 501 nArrayZ: 201
iHyd: 1; dzdr: ************; tauray:************; zRay: ************; ampRay: NaN+j* NaN
; qRay:
Besides being really ugly, it doesn't make much sense to me, as ìh is declared as integer*8 and not as real.
So how can i solve this?
I'm counting 6 character&variable specifications in the format statement, but you're printing 8 of them.
edit:
a nicer use of the format statement would be '(A,I3,7(A,E12.8))'
Fortran "recycles" the format if there are more things to be printed than specified in the format statement. If a write statement gives results you don't understand, to diagonose the problem it may be helpful to remove the things printed one at a time until the error goes away.
It says "item 15", which I would take to be down near the end of your list, not ih at the beginning. It's clear that both "w" and "qray" are being printed as REAL; is either one of them an INTEGER? You may need to change the format specifier then.
I do some image processing work in C++. For this i use CImg.h library which i feel is good for my work.
Here is small piece of code written by me which just reads an image and displays it.
#include "../CImg.h"
#include "iostream"
using namespace std;
using namespace cimg_library;
int main(int argc,char**argv)
{
CImg<unsigned char> img(argv[1]);
img.display();
return 0;
}
When i give lena.pgm as input this code it displays the image. Where as if i give some other image, for example ddnl.pgm which i present in the same directory i get "Segmentation Fault".
When i ran the code using gdb i get the output as follows:
Program received signal SIGSEGV, Segmentation fault.
0x009823a3 in strlen () from /lib/libc.so.6
Missing separate debuginfos, use: debuginfo-install glibc-2.9-2.i686 libX11-1.1.4-5.fc10.i386 libXau-1.0.4-1.fc10.i386 libXdmcp-1.0.2-6.fc10.i386 libgcc-4.3.2-7.i386 libstdc++-4.3.2-7.i386 libxcb-1.1.91-5.fc10.i386
Can some one please tell me what the problem is? and how to solve it.
Thank you all
Segfault comes when you are trying to access memrory which you are not allowed to access.
So please check that out in the code.
The code itself looks just fine. I can suggest some ways to go ahead with debugging -
Try removing the display() call. Does the problem still occur? (I'd assume it does).
Try finding out where in the CImg code is the strlen() that causes the segmentation fault (by using a debugger). This may give additional hints.
If it is in the PGM file processing, maybe the provided PGM file is invalid in some way, and the library doesn't do error detection - try opening it in some other viewer, and saving it again (as PGM). If the new one works, comparing the two may reveal something.
Once you have more information, more can be said.
EDIT -
Looking at the extra information you provided, and consulting the code itself, it appears that CImg is failing when trying to check what kind of file you are opening.
The relevant line of code is -
if (!cimg::strcmp(ftype,"pnm")) load_pnm(filename);
This is the first time 'ftype' is used, which brings me to the conclusion that it has an invalid value.
'ftype' is being given a value just a few lines above -
const char *const ftype = cimg::file_type(0,filename);
The file_type() function itself tries to guess what file to open based on its header, probably because opening it based on the extension - failed. There is only one sane way for it to return an invalid value, which would later cause strcmp() to fail - when it fails to identify the file as anything it is familiar with, it returns NULL (0, actually).
So, I reiterate my suggestion that you try to verify that this is indeed a valid file. I can't point you at any tools that are capable of opening/saving PGM files, but I'm guessing a simple Google search would help. Try to open the file and re-save it as PGM.
Another "fun to track down" cause of segmentation faults is compilier mismatches between libraries - this is especially prevalent when using C++ libraries.
Things to check are:
Are you compiling with the same compiler as was used to compile the CImg library?
Are you using the same compiler flags?
Were there any defines that were set when compiling the library that you're not setting now?
Each of these has bitten me in subtle ways before.