You haven’t initialized *str_new so it is just copying str_old to some random address. You need to do either this: or You will have to #include <stdlib.h> if you haven’t already when using the malloc function.
The problem is that you’re attempting to modify a string literal. Doing so causes your program’s behavior to be undefined. Saying that you’re not allowed to modify a string literal is an oversimplification. Saying that string literals are const is incorrect; they’re not. WARNING : Digression follows. The string literal “this is a test” is of an expression of type char[15] (14 … Read more
You don’t have enough space in fn. By strcat’ing on to it you overwrite the end of its stack allocation and into the stack .. hence the segmentation fault. You could try the following instead: You just have to be sure that the whole path and filename can fit into 255 characters. Alternatively you could … Read more
You need to initialize your pointers. Alternatively, use stack-allocated arrays. For example, instead of char *name, do char name[20]. (Note that this will limit your input to 19 characters; use a larger buffer if necessary.) Right now, you are passing uninitialized pointers into scanf() which effectively means that scanf() is going to write to an … Read more
Compile your application with -g, then you’ll have debug symbols in the binary file. Use gdb to open the gdb console. Use file and pass it your application’s binary file in the console. Use run and pass in any arguments your application needs to start. Do something to cause a Segmentation Fault. Type bt in the gdb console to get a stack trace of the Segmentation Fault.
This is due to stream buffering of stdout. Unless you do fflush(stdout) or you print a newline “\n” the output is may be buffered. In this case, it’s segfaulting before the buffer is flushed and printed. You can try this instead: or:
On CoreOS, solved the problem with.
Arrays are indexed from 0, so the loops should be for(i = 0; i<9; i++) and not for(i = 1; i<10; i++) In your case, you probably override part of the stack, but in general, going out of boundaries results in undefined behavior.
This happens when a python extension (written in C) tries to access a memory beyond reach. You can trace it in following ways. Add sys.settrace at the very first line of the code. Use gdb as described by Mark in this answer.. At the command promptgdb python (gdb) run /path/to/script.py ## wait for segfault ## (gdb) backtrace ## stack trace of the c code
The SIGSEGV signal indicates a “segmentation violation” or a “segfault”. More or less, this equates to a read or write of a memory address that’s not mapped in the process. This indicates a bug in your program. In a Python program, this is either a bug in the interpreter or in an extension module being … Read more