Passing A Stream Through A Function :: C Development :: Discussion Forum :: Networks

Networks » Discussion Forum » C Development » Passing A Stream Through A Function

JavaScript is not enabled on your browser and in order to properly use Coder Profile JavaScript is required.
To view instructions on how to enable JavaScript on your browser click here.

Posted: 3.2 Years Ago

Yuripro84
United States

Contrib Level: 10
Total Posts: 1,132

Hey guys, so I'm totally lost here. I'm almost done w/ an assignment, and have just one last thing to do. He had a working script but wanted us to modify it so instead of writing to the screen we write to a file, and instead using the predefined libraries, we only use the stdio library (he used <iostream> to read/write which is a bit different, I can tell). Anyways, it all seems to be working good, I can read and write what I need, But, I am having problems passing the stream through a function. Here's the original code, followed my my code (a Work in Progress). The error is on line 64. All I need to know, if someone could help, is how to properly pass the stream through the function, and then how to setup the function parameters to allow it. I appreciate all help, this has been bugging me for a long time now and it's due today lol. And I know my code is a bit messy, I'm sorry, I'm in a rush to help some people out in 40mins, still need to get ready and drive there, but thought I'd post this before I left, thanks guys!

-Chris

My Code

CODE:

Copy / Restore

#include <fstream>
#include <iomanip>
using namespace std;
const int MaxHolidays = 25;
const int MaxDescLength = 40;
struct holidayStruct {
int holidayId;
char description[MaxDescLength+1];
int month;
int day;
double cost;
};
holidayStruct *
readHoliday(istream &holidayFile)
{
int id;
holidayStruct *holidayPtr;
holidayFile >> id;
if (!holidayFile.eof()) {
holidayPtr = new holidayStruct;
if (!holidayPtr) {
// cerr << "Critical Error: Failure to allocate memory in "
// << "readHoliday() function.\n"
// << "Contact your holiday management program team to resolve\n"
// << "this problem." << endl;
exit(1);
}
holidayPtr->holidayId = id;
holidayFile >> holidayPtr->month >> holidayPtr->day >> holidayPtr->cost;
holidayFile.ignore();
holidayFile.getline(holidayPtr->description, MaxDescLength+1);
return (holidayPtr);
} else return NULL;
}
int
main()
{
holidayStruct *items[MaxHolidays];
holidayStruct *itemPtr = NULL;
int i; // general loop counter
int itemCount; // current number of items
char str[100];
FILE * holidays;
holidays = fopen ("holidays.txt","r");
FILE * partsOut;
partsOut = fopen ("partsOut.txt","w");
if(holidays==NULL)
printf("%s","Could Not Open File");
//reading from the file
itemCount = 0;
// fscanf(holidays,"%s",&str);
//printf("%s",str);
while (itemCount < MaxHolidays && (items[itemCount] = readHoliday(&holidays)) )
++itemCount;
// cout << itemCount << " holidays read in.\n";
// cout << setiosflags(ios::fixed);
// cout.precision(2);
//if (itemCount)
fprintf(partsOut,"%*s %*s %*s %*s %s",
10, "id",
10,"Month",
10,"Day",
12,"Cost",
"Description\n");
// cout << setw(10) << "id" << setw(10) << "Month"
// << setw(10) << "Day" << setw(12) << "Cost"
// << " Description\n\n";
for(i=0; i<itemCount; i++)
// cout << setw(10) << items[i]->holidayId
// << setw(10) << items[i]->month
// << setw(10) << items[i]->day
// << setw(12) << items[i]->cost
// << " " << items[i]->description << endl;
gets(str);
return 0;
}

Select what you want to copy and in doing so you will keep the formatting when pasting it.

#include <fstream>
#include <iomanip>
using namespace std;
 
const int MaxHolidays = 25;
const int MaxDescLength = 40;
 
struct holidayStruct {
    int holidayId;
    char description[MaxDescLength+1];
    int month;
    int day;
    double cost;
};
 
holidayStruct *
readHoliday(istream &holidayFile)
{
    int id;
    holidayStruct *holidayPtr;
    
    holidayFile >> id;
    if (!holidayFile.eof()) {
        holidayPtr = new holidayStruct;
        if (!holidayPtr) {
//            cerr << "Critical Error: Failure to allocate memory in "
//                 << "readHoliday() function.\n"
//                 << "Contact your holiday management program team to resolve\n"
//                 << "this problem." << endl;
            exit(1);
        } 
        holidayPtr->holidayId = id;
        holidayFile >> holidayPtr->month >> holidayPtr->day >> holidayPtr->cost;
        holidayFile.ignore();
        holidayFile.getline(holidayPtr->description, MaxDescLength+1);
        return (holidayPtr);
    } else return NULL;
}
 
int
main()
{
    holidayStruct *items[MaxHolidays];
    holidayStruct *itemPtr = NULL;
 
    int i;                // general loop counter
    int itemCount;       // current number of items
  
  char str[100];    
  FILE * holidays;
  holidays = fopen ("holidays.txt","r");
  FILE * partsOut;
  partsOut = fopen ("partsOut.txt","w");
  
  if(holidays==NULL)
    printf("%s","Could Not Open File");
  
 
 
    //reading from the file
    itemCount = 0;
  //  fscanf(holidays,"%s",&str);
    //printf("%s",str);
    while (itemCount < MaxHolidays && (items[itemCount] = readHoliday(&holidays)) )
        ++itemCount;
//    cout << itemCount << " holidays read in.\n";
    
//    cout << setiosflags(ios::fixed);
//    cout.precision(2);
 
    //if (itemCount)
      fprintf(partsOut,"%*s %*s %*s %*s  %s",
                       10, "id",
                       10,"Month",
                       10,"Day",
                       12,"Cost",
                       "Description\n");
//        cout << setw(10) << "id" << setw(10) << "Month"
//             << setw(10) << "Day" << setw(12) << "Cost"
//             << "  Description\n\n";
             
    for(i=0; i<itemCount; i++)
      
//        cout << setw(10) << items[i]->holidayId
//             << setw(10) << items[i]->month
//             << setw(10) << items[i]->day
//             << setw(12) << items[i]->cost
//             << " " << items[i]->description << endl;
    gets(str);
    return 0;
}

Original Code

CODE:

Copy / Restore

#include <iostream>
#include <fstream>
#include <iomanip>
using namespace std;
const int MaxHolidays = 25;
const int MaxDescLength = 40;
const char HOLIDAY_FILE[] = "holidays.txt";
struct holidayStruct {
int holidayId;
char description[MaxDescLength+1];
int month;
int day;
double cost;
};
holidayStruct *
readHoliday(istream &holidayFile)
{
int id;
holidayStruct *holidayPtr;
holidayFile >> id;
if (!holidayFile.eof()) {
holidayPtr = new holidayStruct;
if (!holidayPtr) {
cerr << "Critical Error: Failure to allocate memory in "
<< "readHoliday() function.\n"
<< "Contact your holiday management program team to resolve\n"
<< "this problem." << endl;
exit(1);
}
holidayPtr->holidayId = id;
holidayFile >> holidayPtr->month >> holidayPtr->day >> holidayPtr->cost;
holidayFile.ignore();
holidayFile.getline(holidayPtr->description, MaxDescLength+1);
return (holidayPtr);
} else return NULL;
}
int
main()
{
holidayStruct *items[MaxHolidays];
holidayStruct *itemPtr = NULL;
int i; // general loop counter
int itemCount; // current number of items
ifstream inputFile;
inputFile.open(HOLIDAY_FILE, ios::in);
if (inputFile.fail())
{
cerr << "Holiday file " << HOLIDAY_FILE
<< " could not be opened." << endl;
cin.get();
exit(1);
}
//reading from the file
itemCount = 0;
while (itemCount < MaxHolidays
&& (items[itemCount] = readHoliday(inputFile)) )
++itemCount;
cout << itemCount << " holidays read in.\n";
cout << setiosflags(ios::fixed);
cout.precision(2);
if (itemCount)
cout << setw(10) << "id" << setw(10) << "Month"
<< setw(10) << "Day" << setw(12) << "Cost"
<< " Description\n\n";
for(i=0; i<itemCount; i++)
cout << setw(10) << items[i]->holidayId
<< setw(10) << items[i]->month
<< setw(10) << items[i]->day
<< setw(12) << items[i]->cost
<< " " << items[i]->description << endl;
return 0;
}

Select what you want to copy and in doing so you will keep the formatting when pasting it.

#include <iostream>
#include <fstream>
#include <iomanip>
using namespace std;
 
const int MaxHolidays = 25;
const int MaxDescLength = 40;
const char HOLIDAY_FILE[] = "holidays.txt";
 
struct holidayStruct {
    int holidayId;
    char description[MaxDescLength+1];
    int month;
    int day;
    double cost;
};
 
holidayStruct *
readHoliday(istream &holidayFile)
{
    int id;
    holidayStruct *holidayPtr;
    
    holidayFile >> id;
    if (!holidayFile.eof()) {
        holidayPtr = new holidayStruct;
        if (!holidayPtr) {
            cerr << "Critical Error: Failure to allocate memory in "
                 << "readHoliday() function.\n"
                 << "Contact your holiday management program team to resolve\n"
                 << "this problem." << endl;
            exit(1);
        } 
        holidayPtr->holidayId = id;
        holidayFile >> holidayPtr->month >> holidayPtr->day >> holidayPtr->cost;
        holidayFile.ignore();
        holidayFile.getline(holidayPtr->description, MaxDescLength+1);
        return (holidayPtr);
    } else return NULL;
}
 
int
main()
{
    holidayStruct *items[MaxHolidays];
    holidayStruct *itemPtr = NULL;
 
    int i;                // general loop counter
    int itemCount;       // current number of items
    ifstream inputFile;
 
    inputFile.open(HOLIDAY_FILE, ios::in);
    if (inputFile.fail())
    {
        cerr << "Holiday file " << HOLIDAY_FILE
             << " could not be opened." << endl;
        cin.get();
        exit(1);
    }
 
    //reading from the file
    itemCount = 0;
    while (itemCount < MaxHolidays
        && (items[itemCount] = readHoliday(inputFile)) )
        ++itemCount;
    cout << itemCount << " holidays read in.\n";
    
    cout << setiosflags(ios::fixed);
    cout.precision(2);
 
    if (itemCount)
        cout << setw(10) << "id" << setw(10) << "Month"
             << setw(10) << "Day" << setw(12) << "Cost"
             << "  Description\n\n";
             
    for(i=0; i<itemCount; i++)
        cout << setw(10) << items[i]->holidayId
             << setw(10) << items[i]->month
             << setw(10) << items[i]->day
             << setw(12) << items[i]->cost
             << " " << items[i]->description << endl;
 
    return 0;
}

Reply With Quote

Page 1 of 1