help.. string array blows up my pgm

**Deaf Smith** · 07-11-2014

I'm using codeblocks and I defined a string array..

Code:

 char *sname[10];   /* array for student name   */

I loaded the array..

Code:

for ( x = 0; x < ngo; x++ )          // gets info*/
 {
   printf( "\nPlease enter the student name %d ", x);
   scanf("%s", &name);
   sname[x] = name;
   printf( "\nPlease enter the student gpa %d ", x);
   scanf("%d", &sgpa);
   gpa[x] = sgpa;
 }

and then if I try to access it while sorting

Code:

       printf("\n got here to name swap = %d %d %s ", i, j, sname[i]);
       holdname = sname[i];                                              /* swap the name  */
       sname[i] = sname[j];
       sname[j] = holdname;

It fails and gives 'Segmentation fault."

It is NOT the integer (it's well inside the boundary for the 10, but if I try to even
printf, as above, the string array name it blows.Even if I put zero.

Any idea why?

Thanks,

Deaf

**vart** · 07-11-2014

you did not create array of strings - you created array of pointers to string
Then you make each pointer point to the same variable name (which was incorectly use in the previos scanf)

Code:

/* this is string */
char sample[] = "Something read from user and temporarly stored";
/* this is array of 2 strings */
char arr[2][100];
/* and this how you copy string in C */
if(strlen(sample) < 100)
{
   strcpy(arr[0], sample);
}

**Deaf Smith** · 07-11-2014

Ops.. I ment I need an array and each element is a string and not one character for each element.

Each element of the array needs to be a string and not one character.

Sorry about the confusion.

Deaf

**grumpy** · 07-13-2014

Originally Posted by vart

you did not create array of strings - you created array of pointers to string

It's actually an array of pointers to char, not pointers to string. Each of those pointers in the array is uninitialised, so accessing their values (including passing them to I/O functions) results in undefined behaviour.

Thread: help.. string array blows up my pgm

Thread Tools

Search Thread

Display

help.. string array blows up my pgm

Similar Threads

G++ PGO Blows Up

Adding a string array to another string array?

Memory usage blows up

How to copy one string array to another excluding one string

convert char** (c string array) to std::string[]

Tags for this Thread