more switch help

[rewclaus]

I am trying to create a switch function...this is what I have so far:

switch (fixed)
{
case(1): {
fp1 = fopen("somefile.dat", "w");
printf("\"somefile.dat\"");
while(l<6)
{
for (ctr=(l*10); ctr<((l+1)*10); ctr++)
{fprintf(fp1," %d,", deck[ctr]);}
fputs("\n", fp1);
l++;
}
break;
}
case(2): {
fp2 = fopen("otherfile.dat", "w");
printf("\"otherfile.dat\"");
while(l<6)
{
for (ctr=(l*10); ctr<((l+1)*10); ctr++)
{fprintf(fp2, " %d,", deck[ctr]);}
fputs("\n", fp2);
l++;
}
break;
}
default: break;


But for some reason, when I run this witha menu I have created I get a segmentation error when I choose fixed to be 1. When fixed is 2 it works just fine. I get my file no problems. I have all the variables [fixed, l, and fp1, & fp2] defined, and I have all the closing stuff [return, and fclose]. Could someone give me some help please?

-rewclaus

 

[ArkM]

1. Don't use so many braces. The switch statement syntax is much more simpler:

switch (expression)
{
labelled by case/default labels statement sequence
}

For example:

switch (fixed)
{
case 1:
   ...
   break;
case 2:
   ...
   break;
default: /* 0/1 occurence */
   ...
}

2. We can't help you because of we don't know what's l var initial value and what's deck array dimension/extent. Probably you get too large index in fprintf's then catch memory access exception...

 

[Salem]

1. Please use [code][/code] tag when posting code.

2. l is a very poor choice for a variable name, it looks too much like 1.

3. Why don't you use a for loop instead of a while loop?

for ( i = 0 ; i < 6 ; i++ )

4. fp1 = fopen("somefile.dat", "w");
Always check for success.

5. fprintf(fp1," %d,", deck[ctr]);
Your loop iterates 60 times (assuming l starts at 0), yet this strongly suggests you have a deck of cards with the usual 52 entries. Lots of overflow and other nasties here.

Perhaps

for ( i = 0 ; i < 52 ; i++ ) {
  fprintf(fp2, " %d,", deck[i]);
  if ( (i+1)%10 == 0 ) fputs("\n", fp2);
}

--