|
|
 |
|
|
Thread Tools | Display Modes |
Aug 16th, 2006, 8:26 AM
|
#1 |
|
Newbie
Join Date: May 2006
Posts: 18
Rep Power: 0
 |
Segmentation Fault
Hi,
I have the below program which read a file and prints into an output file, It is compiling with out any errrors, but giving a segmentation fault while running it. Can anyone help??
FILE *fp_inFile;
FILE *fp_outFile;
static int iGetSUNFile(FILE*, FILE*);
static int iGetSTARFile(FILE*, FILE*);
static int iGetMOONFile(FILE*, FILE*);
char ctype;
char caoutfile[50]; //output file
/******* Sample main function ********/
int main( int argc, char **argv ) {
/* Checking for correct number of arguments */
if((argc == NULL)||(argc > 3)||(argc < 3)) {
printf("\tErr -> command line\n");
printf("\tUSAGE : FilesDump Type Filename\n");
exit(NG);
}
else {
printf("\tCommand accepted -> Type :[%s] FileName :(%s)\n",argv[1],argv[2]);
}
/* fopen */
if(NULL==(fp_inFile=fopen(argv[2],"rb"))) {
printf("IN File Open Err! -> %s\n",argv[2]);
exit(NG);
}
/* Copying the inputfile name and concatinating ".txt" to the output file */
strcpy(caoutfile, argv[2]);
strcat(caoutfile,".txt");
strcat(caoutfile, "\0");
printf("\tNew FileName = %s\n",caoutfile);
if ((fp_outFile=fopen(caoutfile, "w")) == NULL) {
printf( "OutFile Open Error\n" );
exit( NG );
}
if(strcmp(argv[1],"SUN") == 0) {
ctype=0;
}
else if(strcmp(argv[1],"STAR") == 0) {
ctype=1;
}
else if(strcmp(argv[1],"MOON") == 0) {
ctype=2;
}
/* recognising the type of File Entered at command line */
switch(ctype)
{
case 0 :
if(NULL == iGetSUNFile(fp_inFile, fp_outFile))
exit(NG);
break;
case 1 :
if(NULL == iGetSTARFile(fp_inFile, fp_outFile))
exit(NG);
break;
case 2 :
if(NULL == iGetMOONFile(fp_inFile, fp_outFile))
exit(NG);
break;
default : printf("\tError -> Type must be one of the following – SUN, STAR, MOON \n");
break;
}
exit( OK );
}
/*======================================================================
FUNCTION : Get SUN File
RETURN : OK / NG
======================================================================*/
int iGetSUNFile(FILE* fp_inFile, FILE* fp_outFile)
{
int i,j;
unsigned long ulRecordCount=0, ulDatabaseID=0, ulAlbumID=0, ulVolumeID=0;
unsigned long ulSectionID=0, ulLayerID=0, ulRecordID=0, ulNameRecordCount=0;
unsigned short usNameType=0;
unsigned char ucLanguageCode;
char acString[40];
fread((void *)ulRecordCount,8,1,fp_inFile);
fprintf(fp_outFile, "Record Count : %lu\n", ulRecordCount);
for(i = 0; i< ulRecordCount; i++){
fread((void *)ulDatabaseID, 8, 1, fp_inFile);
fread((void *)ulAlbumID, 8, 1, fp_inFile);
fread((void *)ulVolumeID, 8, 1, fp_inFile);
fread((void *)ulSectionID, 8, 1, fp_inFile);
fread((void *)ulLayerID, 8, 1, fp_inFile);
fread((void *)ulNameRecordCount, 8, 1, fp_inFile);
for(j =0; j<ulNameRecordCount; j++) {
fread((void *)ucLanguageCode, 1, 1, fp_inFile);
fread((void *)usNameType, 2, 1, fp_inFile);
fread((void *)acString, 40, 1, fp_inFile);
fprintf(fp_outFile, "DBID:%lu\t AlbumID:%ul\t VolID:%lu\t SecID:%lu\t LayID:%lu\t \n NameRecordCount:%lu\n LangCode:%us\t NameType:%us\t String:%s\n", ulDatabaseID,ulAlbumID,ulVolumeID, ulSectionID,ulLayerID, ulNameRecordCount, ucLanguageCode, usNameType,acString);
}
}
fclose( fp_inFile);
fclose(fp_outFile);
return( OK );
}
/*======================================================================
FUNCTION : Get STAR File
RETURN : OK / NG
======================================================================*/
int iGetSTARFile(FILE* fp_inFile, FILE* fp_outFile)
{
int i;
unsigned long ulRecordCount=0, ulDatabaseID=0, ulAlbumID=0, ulVolumeID=0;
unsigned long ulDatasetID=0, ulSectionID=0, ulLayerID=0, ulRecordID=0;
fread((void *)ulRecordCount,8,1,fp_inFile);
fprintf(fp_outFile, "Record Count : %lu\n", ulRecordCount);
for(i = 0; i< ulRecordCount; i++) {
fread((void *)ulDatabaseID, 8, 1, fp_inFile);
fread((void *)ulAlbumID, 8, 1, fp_inFile);
fread((void *)ulVolumeID, 8, 1, fp_inFile);
fread((void *)ulDatasetID, 8, 1, fp_inFile);
fread((void *)ulSectionID, 8, 1, fp_inFile);
fread((void *)ulLayerID, 8, 1, fp_inFile);
fprintf(fp_outFile, "DBID:%lu\t AlbumID:%ul\t VolID:%lu\t DatasetID:%lu\t SecID:%lu\t LayID:%lu\t \n", ulDatabaseID,ulAlbumID,ulVolumeID,ulDatasetID, ulSectionID,ulLayerID);
}
fclose( fp_inFile);
fclose(fp_outFile);
return( OK );
}
/*======================================================================
FUNCTION : Get MOON File
RETURN : OK / NG
======================================================================*/
int iGetMOONFile(FILE* fp_inFile, FILE* fp_outFile)
{
int i;
unsigned long ulRecordCount=0, ulDatabaseID=0, ulAlbumID=0, ulVolumeID=0;
unsigned long ulDatasetID=0, ulSectionID=0, ulLayerID=0, ulRecordID=0;
long lLatitude=0, lLongitude=0, lAltitude=0;
fread((void *)ulRecordCount, 8,1,fp_inFile);
fprintf(fp_outFile, "Record Count : %lu\n", ulRecordCount);
for(i = 0; i< ulRecordCount; i++) {
fread((void *)ulDatabaseID, 8, 1, fp_inFile);
fread((void *)ulAlbumID, 8, 1, fp_inFile);
fread((void *)ulVolumeID, 8, 1, fp_inFile);
fread((void *)ulDatasetID, 8, 1, fp_inFile);
fread((void *)ulSectionID, 8, 1, fp_inFile);
fread((void *)ulLayerID, 8, 1, fp_inFile);
fread((void *)lLatitude, 8, 1, fp_inFile);
fread((void *)lLongitude, 8, 1, fp_inFile);
fread((void *)lAltitude, 8, 1, fp_inFile);
fprintf(fp_outFile, "DBID:%lu\t AlbumID:%lu\t VolID:%lu\t DatasetID:%lu\t SecID:%lu\t LayID:%lu\t \n Lat:%d\t Long:%d\t Alt:%d\n", ulDatabaseID,ulAlbumID,ulVolumeID,ulDatasetID, ulSectionID,ulLayerID,lLatitude,lLongitude,lAltitude);
}
fclose( fp_inFile);
fclose(fp_outFile);
return( OK );
} |
|
|
|
Aug 16th, 2006, 9:04 AM
|
#2 |
|
Professional Programmer
Join Date: May 2006
Location: Maryland, USA
Posts: 306
Rep Power: 3
|
Run the program through a debugger, it will stop where the seg fault appears. This will greatly help you, and us fix the problem.
|
|
|
|
|
Aug 16th, 2006, 10:19 AM
|
#3 |
|
Resident Grouch
 
Join Date: Jun 2005
Posts: 6,453
Rep Power: 10
|
Excellent suggestion. There's a good chance that you are putting more in a buffer than you have provided room for, or that you are referring to a non-existent buffer with a bunged-up pointer. Watch those things as you step through or run to a fault. These things can also be isolated with debug printfs, but using a debugger is much more effective. If you are using the debugger that comes with Dev-Cpp (as an example), you will have less visibility of some of these than if you have a more powerful kind. If you can't watch what you want, you can at least isolate the area of the failure and fall back on printfs to fill in the blanks. The salient point here: information is key. When you ask, give detailed error messages, line numbers, where the program SEEMS to be when the failure occurs, reasonable stuff like that. "While it's running" is a tad shy of sufficiency.
__________________
Abstraction doesn't make it impossible to write bad code; it makes it possible to write superior code. Contributor's Corner: Grumpy on C++ Exceptions DaWei on Pointers |
|
|
|
|
Aug 17th, 2006, 1:18 PM
|
#4 |
|
Newbie
Join Date: Aug 2006
Location: Alabama
Posts: 26
Rep Power: 0
|
I think that your problem may be here:
fread((void *)ulRecordCount,8,1,fp_inFile); Suggest maybe &ulRecordCount. Otherwise, ulRecordCount holds the location of memory your attempting to store to. |
|
|
|
|
Aug 17th, 2006, 2:07 PM
|
#5 |
|
Professional Programmer
Join Date: May 2006
Location: Maryland, USA
Posts: 306
Rep Power: 3
|
It looks like all of your fread statements are like that. They should look like:
fread(&ulRecordCount, sizeof(unsigned long), 1, fp_inFile); Like Kennedy said below you are telling fread to write a block of memory at address ulRecordCount, which is actually 0x0 (NULL), at this point. fread can only write into an already allocated buffer. Not to mention that you should check the return value of those statements to make sure you are actually reading something from the file. |
|
|
|
|
Aug 21st, 2006, 4:16 AM
|
#6 |
|
Newbie
Join Date: May 2006
Posts: 18
Rep Power: 0
|
Thankyou All.
|
|
|
|
|
| Bookmarks |
| Currently Active Users Viewing This Thread: 1 (0 members and 1 guests) | |
| Thread Tools | |
| Display Modes | |
|
|
Similar Threads
|
||||
| Thread | Thread Starter | Forum | Replies | Last Post |
| Segmentation Fault | Cipher | C++ | 2 | Feb 21st, 2006 3:10 PM |
| Segmentation fault | rsnd | C++ | 12 | Sep 24th, 2005 11:07 AM |
| segmentation fault on turing strings to uppercase | Jessehk | C++ | 5 | Aug 22nd, 2005 11:26 PM |
| segmentation fault caused by malloc | to66 | C | 7 | Apr 8th, 2005 2:44 PM |
| fprintf segmentation fault | Michael Edgar | C++ | 0 | Mar 21st, 2005 1:21 AM |
Linear Mode
