Not printing string from struct in C

Question

Having a problem with print strings from structs in C... ``` typedef struct box{ char *REF_OR_SYS; int num, x, y, w, h, o; }BOX; sscanf(str, "%s %d %d %d %d %d %d", &label, &refNum, &x, &y, &w, &h, &o); BOX detect = {label, refNum, x, y, w, h, o}; printf("
LABEL IS %s
", detect.REF_OR_SYS); //Prints out the String correctly //(Either the word REF or SYS) return detect; ``` When this is structure is passed to another structure, everything is displayed right EXCEPT for the string.. ``` void printBox(BOX detect){ printf("Type: %s Ref: %d X: %d Y: %d W: %d H: %d O:%d
", detect.REF_OR_SYS, detect.num, detect.x, detect.y, detect.w, detect.h, detect.o); ``` } Am I missing something simple? REF_OR_SYS always prints out as ??_?

Accepted Answer

Use `strdup()` (usually available, if not use `malloc()`) to copy the string read into `label` by `sscanf()`:

```
detect.REF_OR_SYS = strdup(label);
```

as when that function returns `label` is out of scope and `REF_OR_SYS` will be a dangling pointer. Remember to `free()` it when no longer required.

Not printing string from struct in C

Solution

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