C fprintf写多行到文件？

Question

I have school project in Linux and I need to create a user defined text file which has 1000 random numbers between 100-999.

I managed to create user defined file by using array and my code has no errors but when I run it I only have one number in my file but I want to have 1000 numbers I use \\n but its not working please help me ?

#include<stdio.h>
#define MAX 100

int main()
{
    FILE *fp;
    char dosya[MAX];
    printf("\nLütfen dosya adı giriniz:");
    scanf("%s",dosya);
    fp=fopen(dosya,"w");
    int i;
    for (i=0;i<1000;i++);
    {

        int sayi;

        sayi=rand()%999-100;
        fprintf(fp,"\n");
        fprintf(fp,"%d\n",sayi);
        fprintf(fp,"\n");
    }
    fclose(fp);
    return 0;
}

When I run this in my file there is only one number so I think it keeps writing on the same line for 1000 times (but there is /n) where is the rest I checked the for loop and its working please help me ?

Answer 1

Remove semicolon after for loop.

When you execute your code all after all 1000 iterations only one time your block after for loop executes.

for (i=0;i<1000;i++);  
                    ^^   

Answer 2

In C, all instructions are terminated in a semicolon

Your "for" statement has a semicolon at the end, which is interpreted as a "do nothing" instruction.

for (i=0;i<1000;i++);  

Remove the trailing semicolon and it will work.

Answer 3

You are terminating the for loop just after you creating it. remove the semicolon on the line below.

for (i=0;i<1000;i++);

Your final code:

#include<stdio.h>
#define MAX 100

int main(){
FILE *fp;
char dosya[MAX];
printf("\nLütfen dosya adı giriniz:");
scanf("%s",dosya);
fp=fopen(dosya,"w");
int i;
for (i=0;i<1000;i++){ 
    int sayi;
    sayi=rand()%999;
    fprintf(fp,"\n");
    fprintf(fp,"%d\n",sayi);
    fprintf(fp,"\n");
}
fclose(fp);
return 0;

}