Segmentation fault reading string on cin read

In summary, the programmer attempted to read a string from cin. However, when they hit the "cin >> strWord" statement, they received an error message stating "Segmentation fault (core dumped)." After investigating, it was found that the programmer's code had a potential issue with accessing strings that were not within their defined boundaries.
  • #1
OSalcido
66
0

Homework Statement


I'm trying to read a string from cin. When it hits the "cin >> strWord" statement, I get the following error message: Segementation fault (core dumped). The input file is named "data4nine". I'm really not sure what a segmentation fault is and why I'm getting it


The Attempt at a Solution


Code:
	while (!cin.eof())
	{
		cin >> strWord;
		intWords++;
		cntVowsCons(strWord, intVowels, intConsonants);
		strFormatted = FormatWord(strWord);
		lenWords += strWord.length();
		lenFormatted += strFormatted.length();


		if(strFormatted.length() % 2 != 0) 
			SwapMidChar(strFormatted);
		if(istenth(intWords, tenth))
			cout << strFormatted << endl;
		else
			cout << strFormatted;
		
	}
 
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  • #2
Here are my files
 

Attachments

  • hw09.zip
    1.7 KB · Views: 271
  • #3
Segmentation fault is generally a memory access violation. In this case, your program will attempt to access part of a string that doesn't exist (I know where this is in your code, but it should be left as an exercise to you). You may attempt to find it by scrutinizing your code or by using a debugger.
 
  • #4
Hi OSalcido! :smile:

When an access violation (aka segmentation violation) occurs in a program, it may or may not crash with a core dump.
And if it does crash, it's often not a the point where the access violation occurred.

In any program an access violation always occurs in one of 2 forms.

Either you follow a pointer that does not point anywhere.
Since you're not using pointers, that won't be a problem.

Or you are indexing an array outside of its bounds.
Each of your for-loops should be defined such that you can always be sure your string is indexed inside its bounds.
Can you check if that is the case?
 
  • #5
Yes! Thank you guys I did check the loops and fixed the issues. Thanks a bunch
 
  • #6
Your welcome. ;)

Btw, if you use an input of just one word and a newline, or none at all, you may get some results you don't expect.
 

FAQ: Segmentation fault reading string on cin read

What is a segmentation fault when reading a string using cin in C++?

A segmentation fault is a type of error that occurs when a program tries to access a memory address that it is not allowed to access. In the case of reading a string using cin in C++, this can happen if the program tries to access memory that is not allocated for the string or if the string is too large for the allocated memory.

How can I fix a segmentation fault when reading a string using cin in C++?

To fix a segmentation fault when reading a string using cin in C++, you will need to carefully check your code for any potential issues. This can include making sure you have allocated enough memory for the string, checking for any out-of-bounds access, and using the correct syntax for reading the string. You may also need to use debugging tools to help identify the exact cause of the error.

What are some common causes of a segmentation fault when reading a string using cin in C++?

Some common causes of a segmentation fault when reading a string using cin in C++ include forgetting to allocate memory for the string, trying to access memory outside the bounds of the allocated memory, and using incorrect syntax for reading the string. It can also be caused by other errors in the program that affect memory access.

Can a segmentation fault when reading a string using cin in C++ be caused by user input?

Yes, a segmentation fault when reading a string using cin in C++ can be caused by user input. If the user enters a string that is too large for the allocated memory or contains special characters that are not handled properly by the program, it can result in a segmentation fault. It is important to have error handling in place to prevent this from happening.

How can I prevent a segmentation fault when reading a string using cin in C++?

To prevent a segmentation fault when reading a string using cin in C++, you should make sure to properly allocate memory for the string, use correct syntax for reading the string, and handle any potential errors or edge cases in user input. It is also helpful to use debugging tools to catch any errors before they result in a segmentation fault.

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