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POProgramming pointer issue
 

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  1. POProgramming pointer issue
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    <p>I was assigned to do a project that reads from a file and according to the char it inputs is what it does with the following values so if it reads + it will add the next two numbers or if its an H it'll print out the instructions. Im having trouble with printing the results to another file I pass the pointer to each function as follows <code>void add(int a, int b, FILE *print)</code>, and invoke it as follows.. <code>add(a, b, printer)</code>, it worked perfectly before I tried printing out to a file. The error I get is...</p> <p>in function add:</p> <pre><code>error : incompatible type for argument 1 of fprintf expected 'struct FILE *' but argument is of type 'FILE' </code></pre> <p>this happens too all my functions.</p> <p>here's the code. Thanks !</p> <pre><code>#include &lt;stdio.h&gt; #include &lt;stdlib.h&gt; void add(int a, int b, FILE *print); void add(int a, int b, FILE *print) { int c; c = a + b; printf("%i + %i = %i\n\n", a, b, c); fprintf(*print, "%i + %i = %i\n\n", a, b, c); } void subtract(int a, int b, FILE *print); void subtract(int a, int b, FILE *print) { int c; c = a - b; printf("%i - %i = %i\n\n", a, b, c); fprintf(*print, "%i - %i = %i\n\n", a, b, c); } void multiply(int a, int b, FILE *print); void multiply(int a, int b, FILE *print) { int c; c = a * b; printf("%i * %i = %i\n\n", a, b, c); fprintf(*print, "%i * %i = %i\n\n", a, b, c); } void divide(int a, int b, FILE *print); void divide(int a, int b, FILE *print) { double c; c = (double)(a/b); printf("%i - %i = %.1lf\n\n", a, b, c); fprintf(*print, "%i - %i = %.1lf\n\n", a, b, c); } void help(FILE *print); void help(FILE *print) { printf("+ i j [Integer Add]\t\tAdds integers i and j and print out result\n\n"); printf("* i j [Integer Multiply]\tMultiply integers i and j and print out result\n\n"); printf("- i j [Integer Subtract ]\tSubtract integer j from i and print out result\n\n"); printf("/ i j [Integer Divide ]\t\tDivide integer i by j and print out result of integer division\n\n"); printf("H [Help ]\t\t\tPrint a short synopsis of all the available commands\n\n"); printf("Q [Quit ]\t\t\tQuit\n\n"); printf("\n\n"); fprintf(*print, "+ i j [Integer Add]\t\tAdds integers i and j and print out result\n\n"); fprintf(*print, "* i j [Integer Multiply]\tMultiply integers i and j and print out result\n\n"); fprintf(*print, "- i j [Integer Subtract ]\tSubtract integer j from i and print out result\n\n"); fprintf(*print, "/ i j [Integer Divide ]\t\tDivide integer i by j and print out result of integer division\n\n"); fprintf(*print, "H [Help ]\t\t\tPrint a short synopsis of all the available commands\n\n"); fprintf(*print, "Q [Quit ]\t\t\tQuit\n\n"); fprintf(*print, "\n\n"); } char quit(void); char quit(void) { char user; printf("Do you really want to quit?(y/n): "); scanf(" %c", &amp;user); return user; } int main() { char trigger; char user; char fname; char lname; int a; int b; FILE *myPointer; FILE *printer; myPointer = fopen("CommandsProj1.dat", "r"); printer = fopen("results.dat", "w"); if (myPointer == NULL) { printf("error opening the file"); fprintf(printer, "error opening the file"); } else { fscanf(myPointer, " %c%c", &amp;fname, &amp;lname); printf("Initials %c%c\n\n\n", fname, lname); while(user != 'y') { fscanf(myPointer, " %c", &amp;trigger); switch(trigger) { case '+': fscanf(myPointer, "%i%i", &amp;a,&amp;b); add(a,b,myPointer); break; case '-': fscanf(myPointer, "%i%i", &amp;a, &amp;b); subtract(a,b,myPointer); break; case '/': fscanf(myPointer, "%i%i", &amp;a,&amp;b); divide(a,b,myPointer); break; case '*': fscanf(myPointer, "%i%i", &amp;a,&amp;b); multiply(a,b,myPointer); break; case 'H': help(myPointer); break; case 'Q': user = quit(); } } } return 0; } </code></pre>
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    1. USalk
    1. USuser3033804
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    1. This table or related slice is empty.
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    1. PO
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    2. PO
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    1. CODo as the error says, change *print to print in fprintf.
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      1. POProgramming pointer issue
      1. USbenipalj
 

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