saving array to a file won't work, program crashes - c

Question

I posted a few days ago already about a problem with my array-program. Well, it is basically a program which lets the user generate an array, safe a specific number in a specific slot, read the array or read a specific slots value. Now I am figuring out, how to let the user save the current array as a file.
this is what I got
void safeFile(){
FILE *f = fopen("list.txt", "a+");
putc(f , list);
fclose(f);
printf("File saved");
start();
}
where's the problem?
My Program crashes everytime I call the function safeFile() .
I played around, came with fputs instead of putc, program won't crash anymore, the file gets created but it's still blank
void safeFile(){
FILE *f = fopen("list.txt", "r+");
fputs(f , list);
fclose(f);
printf("File saved");
start();
}
here is my current full code
would be grateful for advices, im a newb
#include <stdio.h>
#include <stdlib.h>
int list[30];
int x = 0;
int i = 0; // variable used by for-Loop in setList
int j = 0; // variable used by for-Loop in getList
int input;
int option; //start Value
int gvinput; //getValue input
void start();
void getList();
int main()
{
start();
return 0;
}
void setList(int sizeOfList)
{
for (i = x; i <= sizeOfList; i++)
{
list[i] = i;
}
}
void getList(){
for(j = x; j < i ; j++ )
{
printf("At %d we got the value %d \n",j,list[j]);
}
}
void startList()
{
fflush(stdin);
printf("Please enter number between 0 and 30\n ");
scanf("%d",&input);
if(input > 30 || input == 0)
{
printf("The Number is not between 0 and 30\n");
startList();
}
setList(input);
getList();
fflush(stdin);
start();
}
void setValues(int l[])
{
fflush(stdin);
int v;
int loc;
printf("please enter what value you want to safe\n");
scanf("%d",&v);
fflush(stdin);
printf("Where do you want to save it?\n");
scanf("%d",&loc);
l[loc] = v;
printf("we got at slot %d the value %d\n\n",loc,l[loc]);
start();
}
void getValues(int getArray[]){
fflush(stdin);
printf("which slot do you want to read?\n");
scanf("%d",&gvinput);
fflush(stdin);
printf("The value is: %d \n\n",getArray[gvinput]);
start();
}
void safeFile(){
FILE *f = fopen("list.txt", "r+");
fputs(f , list);
fclose(f);
printf("File saved");
start();
}
void start(){
fflush(stdin);
printf("\n");
printf("[L] = generate Slots\n");
printf("[S] = set a Value at specific slot\n");
printf("[G] = get a Value from a specific slot\n");
printf("[F] = safe File");
printf("[X] = exit\n");
option=getchar();
if(option == 'L' || option == 'l'){
startList();
}
if(option == 'S' ||option == 's'){
setValues(list);
}
if (option =='G' ||option == 'g'){
getValues(list);
}
if (option == 'X' || option == 'x'){
printf("Thank you");
}
if (option == 'f' || option == 'F'){
safeFile();
}

Answer 1

int putc( int ch, std::FILE* stream );
putc writes a single char, and you pass an array of ints to it. The same is true for fputs, which writes a null-terminated string. You'll really have to write some code that serializes your data structure to a sequence of bytes to be written to the file.
In your case, since you want to save a list of ints, you can do this with a loop, for example, that is, loop over your array and write each item to the file. You'll also need a function that writes an int (putc isn't good here, since it writes a char). Have a look at printf, if you'd like to stick with C-style IO, otherwise use streams.

Answer 2

If your using putc(), you should be passing char by char.
for(i=0;i<strlen(list);i++)
{
putc(f,list[i]);
}
The list is an array, if you pass the address it means whole array so putc won't work here.

Answer 3

int fputs(const char *s, FILE *stream);
The second argument to the fputs is the stream. Since u use int [10]. u can use fprintf to print to the file.
Also, fflush(stdin); is undefined behaviour

Answer 4

you need to use the loop, but it is not working because the parameters in the putc function are not in the correct order. Try this:
for(i=0;i<strlen(list);i++)
{
putc(list[i],f); //<---------- NOT putc(f,list[i]);
}
first the char and second the stream.
int putc ( int character, FILE * stream );