Why won't this image be read in from a string?

[goodbadugly16]

what i'm trying to have happen is after i run the program and write in image.txt, i want to have the 4-optioned menu to pop up. however that is not happening. does anyone have any suggestions as to the error? thank you.

#include <stdio.h>

    char inversion(char image[][200], char chars[], int rows, int columns);
    char translation(char image[][200], int up, int right);
    char rotate(char image[][200], int rows, int columns);
    char shrink(char image[][200], int rows, int columns);


int main() {
  int i = 0;
  int j = 0;
  int choice;
  int exit = 0;
  int rows;
  int columns;
  int junk;
  char image[80];

  char chars[12] = {'M','W','B','H','A','S','I','+',';',',','.'};
  FILE *inputr; //input file pointer
  FILE *outp; //output file pointer

        printf("Please enter file name: ");

  //ATTEMPT TO OPEN FILE!
  scanf("%s", image);
  if((inputr = fopen(image,"r")) == NULL) { //if file cannot open
    printf("Could not open image.txt\n");
    return 1;
  } //end if

  else{ //if file opens

    for(i = 0; i < rows; i++){
        fscanf(inputr, "%c", &junk);
    for(j = 0; j < columns; j++){
        fscanf(inputr, "%c", &junk);

    } //end inner for loop
}     //end outer for loop


    fclose(inputr); //close file when done reading it
		////fscanf to read in, also do print
    } //end else


  //ATTEMPT TO CREATE A NEW FILE!
  if ((outp = fopen("finalimage.txt","w")) == NULL) { //if file cannot be created
    printf("Could not open output.dat\n");
    return 1;
  } //end if
  else { //if file creation is successful



    for(i = 0; i < rows; i++){
        fprintf(outp, "%c");
    for(j = 0; j < columns; j++){
        fprintf(outp, "%c");

    } //end inner for
} //end outer for

     fclose(outp); //close file when done writing it
    } //end else

///print array to a new file



    printf("Would you like to:\n\n");
        printf("1. Inversion\n");
        printf("2. Translation\n");
        printf("3. Rotate\n\n");
        printf("4. Shrink-by-2");
        scanf("%d",&choice);

    if(choice > 4 || choice < 1){  /*Stops any possible input that would not process in the program*/
            printf("Invalid Entry, try again");
            scanf("%d",&choice);
    } //end if

     return 0;

    } //end the main

*in case this doesn't make much sense... after the menu pops up, i'm going to select one of the options in order to move the image (made up of text characters) a certain way.

[Salem]

First, get a compiler which will warn you when you screw up printf/scanf formats.
Eg.

$ gcc -Wall bar.c
bar.c: In function ‘main’:
bar.c:35: warning: format ‘%c’ expects type ‘char *’, but argument 3 has type ‘int *’
bar.c:37: warning: format ‘%c’ expects type ‘char *’, but argument 3 has type ‘int *’
bar.c:52: warning: too few arguments for format
bar.c:54: warning: too few arguments for format
bar.c:19: warning: unused variable ‘chars’
bar.c:13: warning: unused variable ‘exit’
bar.c:36: warning: ‘columns’ may be used uninitialized in this function
bar.c:34: warning: ‘rows’ may be used uninitialized in this function

Second, improve your indent style, say something like this

#include <stdio.h>

char inversion(char image[][200], char chars[], int rows, int columns);
char translation(char image[][200], int up, int right);
char rotate(char image[][200], int rows, int columns);
char shrink(char image[][200], int rows, int columns);

int main()
{
    int i = 0;
    int j = 0;
    int choice;
    int exit = 0;
    int rows;
    int columns;
    int junk;
    char image[80];

    char chars[12] =
        { 'M', 'W', 'B', 'H', 'A', 'S', 'I', '+', ';', ',', '.' };
    FILE *inputr;               //input file pointer
    FILE *outp;                 //output file pointer

    printf("Please enter file name: ");

    //ATTEMPT TO OPEN FILE!
    scanf("%s", image);
    if ((inputr = fopen(image, "r")) == NULL) { //if file cannot open
        printf("Could not open image.txt\n");
        return 1;
    }                           //end if

    else {                      //if file opens
        for (i = 0; i < rows; i++) {
            fscanf(inputr, "%c", &junk);
            for (j = 0; j < columns; j++) {
                fscanf(inputr, "%c", &junk);
            }                   //end inner for loop
        }                       //end outer for loop

        fclose(inputr);         //close file when done reading it
        ////fscanf to read in, also do print
    }                           //end else

    //ATTEMPT TO CREATE A NEW FILE!
    if ((outp = fopen("finalimage.txt", "w")) == NULL) {  //if file cannot be created
        printf("Could not open output.dat\n");
        return 1;
    }                           //end if
    else {                      //if file creation is successful
        for (i = 0; i < rows; i++) {
            fprintf(outp, "%c");
            for (j = 0; j < columns; j++) {
                fprintf(outp, "%c");
            }                   //end inner for
        }                       //end outer for

        fclose(outp);           //close file when done writing it
    }                           //end else

///print array to a new file
    printf("Would you like to:\n\n");
    printf("1. Inversion\n");
    printf("2. Translation\n");
    printf("3. Rotate\n\n");
    printf("4. Shrink-by-2");
    scanf("%d", &choice);

    if (choice > 4 || choice < 1) { /*Stops any possible input that would not process in the program */
        printf("Invalid Entry, try again");
        scanf("%d", &choice);
    }                           //end if

    return 0;
}                               //end the main

[anduril462]

EDIT: Beaten!

Crank up the warnings on your compiler. It should complain about using uninitialized variables. Here's the list I got:

$ gcc -Wall menu.c
menu.c: In function ‘main’:
menu.c:34: warning: format ‘%c’ expects type ‘char *’, but argument 3 has type ‘int *’
menu.c:36: warning: format ‘%c’ expects type ‘char *’, but argument 3 has type ‘int *’
menu.c:52: warning: too few arguments for format
menu.c:54: warning: too few arguments for format
menu.c:19: warning: unused variable ‘chars’
menu.c:13: warning: unused variable ‘exit’
menu.c:35: warning: ‘columns’ may be used uninitialized in this function
menu.c:33: warning: ‘rows’ may be used uninitialized in this function

1. You need to initialize rows and cols before you use them in your loops.
2. You call fprintf(outp, "%c"), but you never give it a character to print out, so you end up printing garbage from the stack.
3. Fix your error messages to give correct file names if they don't open.

I modified your first set of loops to print rows and columns before hand, and got this:

$ ./a.out
Please enter file name: image.txt
rows: 134514672 columns: 134513776

Considering your loops are nested, your program is doing 18,094,076,592,636,144 fscanf calls (or fprintfs if you get to the second loop) on my system, most of which are failing, but you never check the return value to see if you reached the end of file. It seems like nothing is happening, but it is...just not what you think. You should get to your menu eventually, but I wouldn't wait for 18 million billion fscanf calls. On a 1GHz proc, that would be on the order of 18 million seconds (probably lots more, but that gives you a rough idea). Initializing rows and columns to zero got me to your menu.