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I can't enter any value when my program runned

I wrote a program in C/Linux but as in the picture I have an issue. How can I solve this?
Thanks for helps.

The picture is:

http://www.filedropper.com/screensho...15-06-30112909

My Codes are:

Code:

#include <stdio.h>



int main()

{

        FILE *ptrFILE;

        int lineNumber = 1, choice, i, totalLineNumber;

        char c;



        if ((ptrFILE = fopen("Test.txt", "r")) == NULL)

        {

                printf("File couldn't open..\n\n");

        }

        

        printf("*-* Content of file *-*\n\n");

        c = fgetc(ptrFILE);

        while (!feof(ptrFILE))

        {

                printf("%c", c);

                if (c == '\n')

                {

                        lineNumber++;

                }

                c = fgetc(ptrFILE);

        }

        printf("\n\nTotal line number : %d\n\n\n\n", lineNumber);

        totalLineNumber = lineNumber;



        printf("Express the line number which you want to display (Enter positive value for at\nthe beginning or vice versa) : ");

        scanf("%d", &choice);

        printf("\n");

        if (choice > 0)

        {

                lineNumber = 0;

                fseek(ptrFILE, 0L, SEEK_SET);

                c = fgetc(ptrFILE);

                while (!feof(ptrFILE))

                {

                        printf("%c", c);

                        if (c == '\n')

                        {

                                lineNumber++;

                                if (lineNumber == choice)

                                {

                                        break;

                                }

                        }

                        c = fgetc(ptrFILE);

                }

                printf("\n\n\n");

        }

        else if (choice < 0)

        {

                lineNumber = 0;

                fseek(ptrFILE, 0L, SEEK_SET);

                c = fgetc(ptrFILE);

                while (!feof(ptrFILE))

                {

                        if (c == '\n')

                        {

                                lineNumber++;

                        }

                        if (lineNumber>totalLineNumber + choice)

                        {

                                printf("%c", c);

                        }

                        c = getc(ptrFILE);

                }

                printf("\n\n\n");

        }



        fclose(ptrFILE);

        return 0;

}

I can't see the picture. Or the problem.
If you have problem with scanf, then try to debug:

Code:

        int rc;



        fprintf (stderr, "we are before 'scanf' be prepared\n");

        fflush (stderr);

        rc= scanf("%d", &choice);

        fprintf (stderr, "scanf returned %d (expected=1) choice=%d\n",

                (int)rc, (int)choice);

        fflush (stderr);

The picture link doesn't work. Can you describe in words what your problem is, and what you expected please.

When I run this program, naturally it wants from me a value to enter... But I cannot enter any value

> But I cannot enter any value

What is the obstacle?

I don't understand. When I compile your program it works fine:

Code:

gcc -Wall lqc.c -o lqc

lqc.c: In function ‘main’:

lqc.c:6: warning: unused variable ‘i’

As you see I only get a warning for an unused variable. Also, when I run the program it works fine (although it crashes with a segfault if there is no file to open - but that's not the issue at hand here):

Code:

./lqc 

*-* Content of file *-*



line1

line2





Total line number : 3







Express the line number which you want to display (Enter positive value for at

the beginning or vice versa) : 1



line1

I guess you're gonna have to be more specific about your issue.

Quote:

Originally Posted by NoWeDoR (Post 5384925)

A new link for the picture

http://www.megafileupload.com/8U5g/S..._09%281%29.png

You're gonna have to work on your screenshot skills buddy, still no picture!

The problem has been solved. I hadn't expressed the file's name correctly to program.

Quote:

Originally Posted by NoWeDoR (Post 5384959)

The problem has been solved. I hadn't expressed the file's name correctly to program.

Ok. Good. But you might want to change this:

Code:

        if ((ptrFILE = fopen("Test.txt", "r")) == NULL)

        {

                printf("File couldn't open..\n\n");

        }

Into something like this:

Code:

        if ((ptrFILE = fopen("Test.txt", "r")) == NULL)

        {

                printf("File couldn't open..\n\n");

                return 1; // <- You should exit the program here to avoid segfault and other nasty stuff!

        }