Line counting in C but exclude empty lines - c

Question

I've got the following program, but there is a problem. First the program part that does not work:
#include <stdio.h>
#include <stdlib.h>
int main()
{
FILE *fp;
FILE *fp2;
char ch;
char fnamer[100];
char fnamer2[100]; //Storing File Path/Name of Image to Display
printf("\n\nPlease Enter the Full Path of the Image file you want to view: \n");
scanf("%s",&fnamer);
fp=fopen(fnamer,"r");
if(fp==NULL)
{
printf("Error!");
exit(1);
}
printf("\n\nPlease Enter the Full Path of the Image file you want to write to: \n");
scanf("%s",&fnamer2);
fp2=fopen(fnamer2,"w");
if(fp2==NULL)
{
printf("Error!");
exit(1);
}
else
{
// printf("test\n");
}
int line_number = 0;
int charsOnLine = 0;
fprintf(fp2, "%d: ", ++line_number); /* put line number in output file */
printf("%d: ", line_number);
while((ch = fgetc(fp)) != EOF )
{
//printf("test2");
fputc(ch,fp2);
printf("%c", ch);
if ( ch != '\n' && charsOnLine ==0 )
{
fprintf(fp2, "%d:", ++line_number ); /* put line number in output file */
printf("%d: ", line_number);
}
// if (ch != '\n' && charsOnLine 0 ){
// fprintf(fp2, "%c", ch);
// printf("%d", ch);
// }
}
fclose;
fclose(fp);
// fclose(fp2);
// getch();
}
The program needs to count the lines, give them a number but skip the blank lines. But here is the problem: when I run this code it gives all the chars a number.

Answer 1

You could use a flag to remember when you have just started a new line. The first time you see a char not equal to '\n', you print the line number and clear the flag.
Something like:
int line_number = 0;
int newLine = 1;
while((ch = fgetc(fp)) != EOF )
{
if (ch == '\n')
{
newLine = 1;
}
else
{
if (newLine)
{
fprintf(fp2, "%d:", ++line_number );
printf("%d: ", line_number);
newLine = 0;
}
}
fputc(ch,fp2);
printf("%c", ch);
}

Answer 2

From what I understand, the program needs to count the lines and append their content.
Then I would search for '\n' char, rather than skipping it with if (ch != '\n')
int main()
{
FILE *fp;
FILE *fp2;
char ch;
char fnamer[100];
char fnamer2[100]; //Storing File Path/Name of Image to Display
printf("\n\nPlease Enter the Full Path of the Image file you want to view: \n");
scanf("%s",&fnamer);
fp=fopen(fnamer,"r");
if(fp==NULL)
{
printf("Error!");
exit(1);
}
printf("\n\nPlease Enter the Full Path of the Image file you want to write to: \n");
scanf("%s",&fnamer2);
fp2=fopen(fnamer2,"w");
if(fp2==NULL)
{
printf("Error!");
exit(1);
}
int line_number = 0;
fprintf(fp2, "%d: ", ++line_number );
while((ch = fgetc(fp)) != EOF )
{
if ( ch == '\n' )
{
fprintf(fp2, "%d: ", ++line_number ); /* put line number in output file */
}
else {
fputc(ch,fp2); /* put the char in the corresponding line */
}
}
fclose(fp);
fclose(fp2);
}