Uninitialised value was created by a heap allocation
c, malloc, pointers, strncpy, valgrind
Solution
You have two mistakes on line 104,
strncpy(inputCopy, input, strlen(input)*sizeof(char));
You need to give strncpy room for the terminating null, so it should be `strlen(input)+1` strncpy isn't guranteed to leave the output buffer null terminated, which seems like a bug in strncpy but it isn't. It was designed to work that way. What strncpy was designed to do was copy a string into an output buffer and then fill the rest of the buffer with zeros., It's not really designed as a 'safe strcpy'
Your other bug is that strncpy takes a character count not a byte count, so it's incorrect to multiply by `sizeof(char).`. Since sizeof(char) == 1, this isn't actually causing problems, but its still the wrong intent.
You were correct to multiply by `sizeof(char)` in the `malloc` on line 99 since `malloc` needs a byte count.
Problem
I have been chasing this bug around, and I just don't get it. Have I forgotten some basic C or something? ``` ==28357== Conditional jump or move depends on uninitialised value(s) ==28357== at 0x4C261E8: strlen (mc_replace_strmem.c:275) ==28357== by 0x4E9280A: puts (ioputs.c:36) ==28357== by 0x400C21: handlePath (myshell.c:105) ==28357== by 0x400B17: handleInput (myshell.c:69) ==28357== by 0x400AAD: acceptInput (myshell.c:60) ==28357== by 0x4009CF: main (myshell.c:33) ==28357== Uninitialised value was created by a heap allocation ==28357== at 0x4C25153: malloc (vg_replace_malloc.c:195) ==28357== by 0x400BDE: handlePath (myshell.c:99) ==28357== by 0x400B17: handleInput (myshell.c:69) ==28357== by 0x400AAD: acceptInput (myshell.c:60) ==28357== by 0x4009CF: main (myshell.c:33) ==28357== (095) void handlePath(char *input) { (096) if(DEBUG_ON) { printf("%s%s\n", "DEBUG_HANDLEPATH: ", input); } (097) (098) char *inputCopy = NULL; (099) inputCopy = (char *)malloc((strlen(input)+1)*sizeof(char)); (100) (101) if(inputCopy==NULL) { (102) die("malloc() failed in handlePath()"); (103) } (104) strncpy(inputCopy, input, strlen(input)*sizeof(char)); (105) printf("%s\n", inputCopy); (106) free(inputCopy); (107) return; (108) } ``` Line 96 prints the parameter "char *input" just fine (DEBUG_ON==1), but line 105 spits out valgrind errors (it does print just fine in the console). "char *input" originates from a getline() grabbing a line of input, and in the case of this function will be something like "path /test/path" without quotes. I can print and manipulate it just fine in preceding functions. What's uninitialized about "char *inputCopy"? Any ideas? Thanks in advance!