Strcpy

A C standard library function: `strcpy` is used to copy non-overlapping, null-terminated strings

Strncpy

A C standard library function: strncpy is used to copy a maximum of n characters of non-overlapping, fixed-width or null-terminated strings

Buffer use size

Example

"They are safer than strcpy by providing the buffer size of the destination similar to strncpy"

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When should Win32/WinAPI types be used vs. Standard C types?

"Strncpy is more recommended that strcpy because protect your code against buffer overflow"

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Structures and Pointers in C - crash when using strcpy

"Use strcpy or add a null terminator after using strncpy;strncpy does not add the null terminator 0 where as strcpy does"

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Strncpy to already created char []

"Use strcpy and check the buffer size by hand;strncpy is a little safer but dangerous in other way"

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Is there a better way of copying a string to a character array with things already in it

"Now with 3 bytes of memory you can use strcpy to copy the string properly;strncpy will not add the terminating null itself in case the n is equal to the size of supplied buffer thus becoming very very unreliable unlike strcpy"

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C program printing weird characters

"Strcpy adds a null terminator so your string ends there;perhaps strncpy is a more useful function for your situation"

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Malloc a 2D array, where each entry is a string, in C

"You have to reserve memory to 0 very wrong to copy strings you have to usr strcpy the correct function nowadays is strncpy is more safe"

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Allocating memory for a string in C using malloc

Version unsafe strcpy

Example

"Strcpy is notoriously unsafe as are it s cousins strcpy_s and strncpy although they are mildly safer than strcpy"

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Is strcpy where src == dest strictly defined?

"In general strncpy is a safer alternative to strcpy"

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Do Strong Types prevent Buffer Overflow?

"Myth 3 strncpy is a safer version of strcpy"

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Why C11 standard doesn't drop unsafe strcat(),strcpy() functions?

"You should use strcpy or strncpy safer than strcpy to copy the string stored in the array between arrays"

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Building char array from a string (C)

"I was exploring around with c regarding strncpy since most people says that it is safer than strcpy additional parameter length to avoid buffer overflows"

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Strncpy & using non-null terminated strings to read stack frame

"I know strncpy is a safer version of strcpy as said here"

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How to use strncpy correctly?

"The easier way is to use the function strncpy which is more secure than just using strcpy"

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Converting a const char* to char* at compile-time

"Notice the routine is strncpy not strcpy;strcpy is unsafe"

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Error when passing arguments and convert it to hexadecimal

"Strncpy is not really a safer strcpy - strncpy is designed for filling fixed-length text fields which means that it does not always nul-terminate the destination"

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Unexpected pointer randomly changes. Why would it change for? Breaks pointer arithmetic

"Strncpy is safer than strcpy"

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Retrieve value from linked list struct give wrong value

"Strncpy is not safer than strcpy it just trades one type of bugs with another"

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Why should you use strncpy instead of strcpy?

"Of course you might still ask whether to use strncpy or strcpy in implementing that abstraction strncpy is safer there provided you fully grok what abstraction strncpy does"

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C strcpy() - evil?

"Strncpy is not safer method to use as strcpy"

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Valgrind error with strcpy

Better checking things

Example

"Strcpy could be better replaced by strncpy which does some bound checking"

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Operator= overloading in C++

"Using strncpy 3 is better than strcpy 3 but things like strlcpy 3 are better still"

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Why is strncpy insecure?

"I.e strncpy is actually better than the simpler strcpy if you are willing to improve the code"

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Check if a string exists in an array, if not then add it to the array in C

Others

Example

Solved the issue with strncpy though i ll use strcpy to improve readability;what i think it happened is that response is being allocated on top of the variable where i wrote the request then it wasn t being completely zero-ed and since strncpy doesn t add the final 0 like strcpy does then response would become a mix of old and new data

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While reading response from a socket, I get what I wrote earlier on it

Actually the situation is a bit dire since neither strcpy nor strncpy are absolutely good functions;by itself strcpy isn t safe since you can t control the output buffer size and strncpy is inefficient since it writes more zeros than what may be desired

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Aborted (core dumped)

But for the example you give the example doesn t matter - if it s going to fail it will be in the initial strlen so strncpy doesn t buy you anything in terms of safety and presumbly strncpy is slower as presumbly strncpy has to both check bounds and for nul and any difference between memcpy and strcpy isn t worth changing code for speculatively

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C strcpy() - evil?

But in this case you need to use strcpy instead of the assignment operator;upd as paulr noted in the comment above strncpy is a way better option

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Is there a direct way of addressing a 2D char array and store strings on them in C

Strcpy will not work if _friendly_name don t have a 0 before position 16;strncpy will be fine

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Will memcpy copy a string correctly?

For instance strncpy is mostly useless it gives you nothing more than strcpy

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Arduino: Empty String when trying to cast a Char[] to String

So that the strncpy is more secure than strcpy

from question  

Strncpy should only be used with fixed length arrays

Strcpy will generally get the job done;strncpy is better if available

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How to put c++ string into char array

Using strncpy is considered safier than strcpy because the second one can easily cause buffer overrun

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Why this code "initialize character" Cant work?

Never use strcpy;strncpy is safer but still not that safe because it may not append a null character to your buffer

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Pointer and memory issue in c

Strncpy is more safe than strcpy because you limit the amount of bytes to be copied thus avoiding a buffer overflow

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How to pass a 2D Char array to another function?

The best solution is to write a custom version of strncpy that is less weird or if you know the length of the input just use strcpy

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C: How to copy over null terminator to structure member, in cleaner way?

It was never intended to be a safe version of strcpy but is often misused for such purposes;it is in fact considered to be much more dangerous than strcpy since the null termination mechanism of strncpy is not intuitive and therefore often misunderstood

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* (no title is found for this review)

Merged by junio c hamano -- gitster -- in commit e28daf2 15 aug 2018 banned.h mark strncpy as banned the strncpy function is less horrible than strcpy but is still pretty easy to misuse because of its funny termination semantics

from question  

What is the best alternative to strncpy()?

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