Question

I need to write a program that reads from stdin and only writes non-empty lines to stdout (i.e. lines that only contain \n). For example, if the stdin was:

1

2

\n

3

The output would be:

1

2

3

This is what I have so far:

#include <stdio.h> 
#include <string.h> 

int main()

{
    char buf[BUFSIZ];
    char *p;

    printf ("Please enter some lines of text\n");

    if (fgets(buf, sizeof(buf), stdin) != NULL)
    {
        printf ("%s\n", buf);
        /*
         *  Remove newline character
         */
        if ((p = strchr(buf, '\n')) != NULL)
            *p = '\0';
    }
    return 0;
}

Is there any way that I can loop the program around though, so that even if a blank line is entered, the user can still keep inputting?

Answer 1

#include <stdio.h>

int main(void){
    char buf[BUFSIZ];

    printf ("Please enter some lines of text\n");

    while(fgets(buf, sizeof(buf), stdin) != NULL){
        if(*buf != '\n')
            printf("%s", buf);
    }
    return 0;
}