I return to C programming after 12 years and forgot many things.
In my C program I see:
But I cannot find the code, I want to know how it works. An idea?Code:#define ORA_CHECK_COMMIT(lda) \ if(ocom(lda)) { \ handle_error(EM_ORACLE, NULL, "ocom at", __LINE__); \ exit(3); }
Thanks,
What do you mean "find the code"?
It's right there in front of you.
If you see in the actual source something like
ORA_CHECK_COMMIT(banana)
The compiler will replace it with
Code:if(ocom(banana)) { handle_error(EM_ORACLE, NULL, "ocom at", __LINE__); exit(3); }
If you dance barefoot on the broken glass of undefined behaviour, you've got to expect the occasional cut.
If at first you don't succeed, try writing your phone number on the exam paper.
I know it is preprocessor command, which will be replaced by
But I cannot find anywhereCode:if(ocom(lda)) { \ handle_error(EM_ORACLE, NULL, "ocom at", __LINE__); \ exit(3); }
Are they function? Where they can be found, in another program, or header file or somewhere else?Code:ocom(lda) and handle_error
Yes, both ocom() and handle_error() are functions or further macros.
Both will almost certainly be in a header file - unless your code is so old it's full of implicit function declarations.
Both functions will have to be in a library somewhere, otherwise your code will not build.
Which compiler are you using?
If you dance barefoot on the broken glass of undefined behaviour, you've got to expect the occasional cut.
If at first you don't succeed, try writing your phone number on the exam paper.
The code is more than 14 years old. It is AIX, compiler cc
ocom() and others not in header. there is should be a library somewhere.
Well if this were gcc, I would suggest
gcc -E prog.c
to find out what ocom() and handle_error() actually become after the pre-processor has done all it's work.
To find the library, the handy linker option --trace-symbol would be great.
ld(1): GNU linker - Linux man page
Do you have even a basic tool like nm (nm(1): symbols from object files - Linux man page) to show you all the symbols in an object file / library file?
If you dance barefoot on the broken glass of undefined behaviour, you've got to expect the occasional cut.
If at first you don't succeed, try writing your phone number on the exam paper.
I put below just several lines example on Solaris
Could you please explain briefly, what it means?Code:nm -AgrR *.o fin2ici.o: [37] | 0| 0|NOTY |GLOB |0 |UNDEF |fin2ici.o:__iob fin2ici.o: [84] | 4| 268|OBJT |GLOB |0 |4 |fin2ici.o:$XAbOEmKTeX_WEsq.oci_func_tab fin2ici.o: [23] | 4055| 12|OBJT |GLOB |0 |5 |fin2ici.o:$XBbOEmKTeX_WEsq.d2i_CloseMq.__func__ fin2ici.o: [54] | 3962| 16|OBJT |GLOB |0 |5 |fin2ici.o:$XBbOEmKTeX_WEsq.d2i_CloseOracle.__func__ fin2ici.o: [46] | 3996| 17|OBJT |GLOB |0 |5 |fin2ici.o:$XBbOEmKTeX_WEsq.d2i_LeftPadField.__func__ fin2ici.o: [44] | 4013| 15|OBJT |GLOB |0 |5 |fin2ici.o:$XBbOEmKTeX_WEsq.d2i_OpenCursor.__func__
Try the manual page for 'nm' on your system.
If you dance barefoot on the broken glass of undefined behaviour, you've got to expect the occasional cut.
If at first you don't succeed, try writing your phone number on the exam paper.
I was looking for nm options, which shows me the path to our function/libraries. man nm says it is -A. It mentioned function names, but no path. Does it mean that they are also macro? And how can I understand it?
Macro definitions won't appear in an nm list.
All I can suggest is create some simple source files (say a main + one function), then use nm to examine the .o file, until you can grok the output of nm sufficiently well to understand it.
If you dance barefoot on the broken glass of undefined behaviour, you've got to expect the occasional cut.
If at first you don't succeed, try writing your phone number on the exam paper.
Sorry, but I have 3 days to analyze the code, which was written 15 years ago. I cannot play. I have to work.
Thanks
Suggest your employer finds someone competent at C as of now, not someone with a decade of rust to knock away.
If the code has managed for 15 years, why the sudden panic to do something in 3 days?
If you dance barefoot on the broken glass of undefined behaviour, you've got to expect the occasional cut.
If at first you don't succeed, try writing your phone number on the exam paper.
