Whenever I attempt keyboard input into some char arrays, my program ends up crashing.
What's a straightforward way of reading char arrays from the keyboard and saving them?
int main() {
int pos;
char *labels[8];
for (pos=0; pos<8; ++pos) {
scanf("%s",labels[pos]);
}
for (pos=0; pos<8; ++pos) {
printf("%s\n",labels[pos]);
}
return 0;
}The declaration char *labels[8] creates a pointer array. Without initialization to a valid address, those pointers designate invalid locations in memory. Consequently, attempting writes through them results in undefined behaviour.
Before using those pointers, make certain that they reference valid allocated memory locations.
Those pointers form an array pointing to char, but they aren't referncing any valid memmory.
First allocate storage for those pointers:
int main(void)
int pos;
char *labels[8];
for (pos=0; pos<8; ++pos) {
labels[pos]=malloc(LABELCAP);
scanf("%17s",labels[pos]);
}
for (pos=0; pos<8; ++pos) {
printf("%s\n",labels[pos]);
free(labels[pos]);
}
return 0;
}another option is
int main(void) {
int pos;
char labels[8][LABELCAP];
for (pos=0; pos<8; ++pos) {
scanf("%17s",labels[pos]);
}
for (pos=0; pos<8; ++pos) {
printf("%s\n",labels[pos]);
}
return 0;
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