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--- cplusplus:file_processing_examples [2017/02/08 20:51] – [Simple example] mithat
+++ cplusplus:file_processing_examples [2019/02/11 19:17] (current) – [Using filenames] mithat
@@ Line 60: / Line 60: @@
 </file>
-==== Filenames must be c_str in pre-C++11 ====
+==== Using filenames ====
 <file c++ simple-file-write3.cpp>// This program writes data to a file.
@@ Line 79: / Line 79: @@
     cin >> filename;
-    outfile.open(filename.cstr());   // associate file with file pointer object
+    outfile.open(filename);            // associate file with file pointer object
+    //outfile.open(filename.c_str());  // convert filename to C-string in pre-C++11
     if (!outfile)
@@ Line 139: / Line 140: @@
 #include <iostream>
 #include <fstream>
-#include <cstring>
+#include <string>
 using namespace std;
@@ Line 175: / Line 176: @@
 #include <iostream>
 #include <fstream>
-#include <cstring>
+#include <string>
 using namespace std;
@@ Line 183: / Line 184: @@
     int num1;
-    ifstream infile;   // instantiate file pointer object
+    ifstream infile;         // instantiate file pointer object
-    infile.open(filename.c_str());   // associate file with file pointer object
+    infile.open(filename);   // associate file with file pointer object
     if (!infile)
-        cerr << "Error opening file." << endl;
-    else
     {
-        cout << "Reading from file ... " << endl;
+        cout << "Error opening file." << endl;
+        return 1;  // exit program with error code
+    }
-        while (infile >> num1)
+    cout << "Reading from file ... " << endl;
-        {
-            cout << num1 << endl;
-        }
-        infile.close();    // close the file!
-        cout << "Done!" << endl;
+    while (infile >> num1)
+    {
+        cout << num1 << endl;
     }
+    infile.close();    // close the file!
+    cout << "Done!" << endl;
     return 0;
 }
 </file>