[linux] Help please:gdb:Ako debugovat chyby vzniknute pocas navratu z funkcie [resp vo vunkcii ???()]?

Pátek Listopad 29 16:16:07 CET 2002

Vazeny kolegovia!

Potreboval by poradit ako zistit, kde je chyba v kode.. Prejavuje sa tak, ze
volam funkciu, tato prebehne az na koniec no nenastane navrat do volajuce
funkcie...
pricom po gdb pokus core dostavam vystup...

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This GDB was configured as "i386-redhat-linux"...
(no debugging symbols found)...
Core was generated by `pokus'.
Program terminated with signal 11, Segmentation fault.
#0  0x5c616c73 in ?? ()
(gdb) bt
#0  0x5c616c73 in ?? ()
Cannot access memory at address 0x2a0061.
(gdb) quit

CODE 1: Je volajuci kod a sposob zistenia, ze som sa nevratil do
CODE 2:  Je volany kod
VYPIS je subor demostrujuci, ze posledny vypis z CODE 2: prebehol, ale
program sa nevratil do nadradeneho kodu...(koniec vypisu), V  subore vidno,
ze           v programe je okrem vykonavameho kodu aj  obsluha SIG_USR1
(funkcia Prisli Data) a Event handler udalosti Expose instancie triedy
coreWidgetClass, ktoru vyuzivam ako kresliacu plochu (kreslim pomocou X-lib)
X-WINDOWS aplikacie, (funkcia vykresliGokno...).

S gdb nemam velke skusenosti.. Nevie mi niekto poradit ako debugovat tento
kod...
Napada ma jedine chyba pri swap-ovani jadra 2.0.35 (koli HW musim pouzivat
2.0.3x), ale neviem ako zabranit swap-ovaniu kodu...

Vrela vdaka za kazdu radu..

S pozdravom

Peto

CODE 1:

....
  fp=fopen("prepinam OK","at");
  fprintf(fp,"11a.1\n\n");
  fclose(fp);
  zobraz_plan("./002.rez");
 fp=fopen("prepinam OK","at");
 fprintf(fp,"11b.1\n\n");
 fclose(fp);
....

CODE 2:

void zobraz_plan(char *meno_planu)
{
    long flag=0;
    char prikaz[12];
    double oldX,oldY,X,Y,R,otocUhol,startUhol,koniecUhol;
    // Zisti velkost
    FILE *planik,*fp;
    int i;
    idemPrekladam=1;
    idemWW=1;
    ......
    idemWW=0;
    sleep(1);
    vykresliGokno(GRAFICKE_OKNO,NULL,NULL,0);
  fp=fopen("prepinam OK","at");
       fprintf(fp,"\n\n\n\nTretie zobrazenie!!!!!!!!\n");
  fclose(fp);
    idemPrekladam=0;

  fp=fopen("prepinam OK","at");

       fprintf(fp,"\n\n\n\nUplny vystup z prekladu !!!!\n");
  fclose(fp);

}

VYPIS:

  Prisli DATA !!!!
-12.1  0

11.1

11a.1

Uplny vstup do VykresliGokno !!!!

SOM TU !!!!