I have data that is coming into my buffer via popen (process data, not a file). Every seven records is a new set [0-6]. I am trying to 'print out the array line/element value' and 'change the value of element [2] to 0', but my loop appears to be looping through every character and not just every line?
199729173
2014-11-16 10:09:34
Found String!
198397652
2014-11-14 15:10:10
Found String!
198397685
2014-11-14 15:10:13
Found String!
198398295
2014-11-14 15:11:14
Found String!
I have data that is coming into my buffer via popen (process data, not a file). Every seven records is a new set [0-6]. I am trying to 'print out the array line/element value' and 'change the value of element [2] to 0', but my loop appears to be looping through every character and not just every line?
I have a file which contains a year and the name of an associated file to be read. I need to extract the data in the txt file and perform some calculations.
（ year data file） 2004 2004data.txt 2005 2005data.txt 2006 2006data.txt
Here is what I do. I first declare "char yeardata" and then pass "2004data.txt" to it. Then I call yeardata in ifstream to extract the data inside the file "2004data.txt". The problem is that char yeardata is not constant so I cannot pass the file to it. It doesn't work if I change "char yeardata" to "const char yeardata".
Code: int oldnewcomp_temp(char* lcfile) { using namespace std;
I want to use a const char* as a buffer. I am reading values from a file and adding them to a buffer. How to extract the values is simple enough. I am reading through a filestream, reading each character into a char pointer and progressing that char pointer every time. I have another char pointer marking the start positon
eg.
char *mychar = new char; char *char1 = new char; char *char2 = new char; const char *constchar ; char2 = char1; while(filestream.read(mychar,1) { *char1 = *mychar; ++char1; }
Then I get this problem: constchar = mychar; // const char* = char*.
Constchar does not catch all the data in other words. At some stage some data is lost due to zeros in the data.. How can I put values into a const char and get around this problem? The const char* will //only record everything up until the first zero.
I'm currently finishing up an assignment that was half written by my professor. Below in the testGrades section of code there are two errors both are the same message.
Error: no matching function for call to Grades:: Grades(const char [15])
Test Grades
//Purpose: Test program for the class Grades // Create stu1 Grades object // Add 5 grades to stu1 - only 3 can be stored in stu1 - other 2 discarded // Create stu2 Grades object // Add only 2 grades
What is the programmers responsibility with respect to const char * returned by various functions, like the C++ string class c_str() function which returns a const char * to an c style string array? In VC++ I cannot delete a const char * which holds a string literal. Take the following code for example:
Code: void func() //a useless function with illustrative code { string s1("abcd"); string s2("efgh"); const char * cc1 = s1.c_str(); //c_str() returns a const char * c style string pointer s2.c_str(); //this returns a const char *, which must be allocated on the heap right? delete cc1; //produces run time error in Release mode in VC++ }
The problem with the above code snip is that space is allocated on the heap (or so I believe) for the const char *'s returned by the 2 calls to c_str(). The delete attempt fails and there is no opportunity to delete the space allocated by const char * because its not assigned to anything (however I see c_str() used this way extensively)
So, if I cannot delete a const char *, how does the memory get recovered? Perhaps the string objects s1 and s2 themselves have pointers to the items on the heap made by c_str() calls and they get deleted by the destructors of s1 and s2 when the function ends?
Write a program to read in a sequence of characters one by one. Print out the characters in reverse. You should use a char[]. (Remember single quotes are used for char)
For example:
Please enter characters one by one: (Enter 0 to exit) h e l l o 0 You entered: hello. The reverse of that is olleh.
and this is currently my code
#include <iostream> #include <cstdlib> #include <cstdio> #include <ctime> #include <cmath> using namespace std; int main() { char entry[20];
[code]....
im just not sure how to set that value and still make the for loops work
I have a class that defines a window (a popup dialog of sorts), and I want the name of that window to be constant. The only problem is that the name of the popup needs to match the title of the parent window, and I get the name of the parent in the constructor. So how do I go about defining this member variable to be constant and initializing it with a value in the constructor?
I want to do something like this, but I know this isn't allowed:
/* class.h */ class foo { public: foo(*parentWindowPtr);
[Code] .....
I should mention that yes the name of the parent window is const char *, and I would like to keep it this way.
I've been in a strange problem. Im in need to have a dynamic character size, but that increases the outputsize of my program by almost 50kb. (while the program was 11kb previously).
I am a newbie to C++ and VS ++. I have created a windows form application by dragging and dropping button, label..etc. i wish label text to be appeared as return value from a function. The function returns ' const char* '.how this returned string pointer can be used to display label text.?
Are there other ways of calling a const/non-const override? I want to defined some functions in terms of others, particularly accessors which might or might not require constness- in order to not copy & paste code. This is my current solution:
difference between const and static const, more effectively. I know the basic concept of const and static but I need clear explanation of declaring "const" and "static const"
Is there any way to cast a non-const variable to const one?
I want to read variable n from file and then use it to declare array "int arr[n]", but because n is non-const, the compiler doesn't allow me to do that.
Ok so I am back in school and it has been to long since I have used c++ I can not find or figure out how to convert a char array into a int array so i can add numbers really large numbers. the string is being passed into the function as a const char*...
If I have an array of some class, and that class has const members, is there some way I can call a custom constructor on elements of the array?
I can't seem to reinitialize an element in foos in the example below. A thread on stack overflow mentioned the copy constructor show allow it, but I get "no match for call to '(Foo) (Foo&)'" when I try it.
I'm trying to write a program that takes input from the user (thats a char) and outputs it to the monitor in hex form.The program is meant to continuously take input from the user then output to the monitor in hex form until an EOF is detected this triggers the program to close.The following code does this except that I get a lower case 'a' at the end of each output.I think the 'a' has to do with the enter key and if that is the case how can i tell the program to ignore this input from the user.
Example: input from user: ABC output to monitor: 41 42 43 a
I've made a code to check whether or not a save file has been created correctly, but for some reason it always returns this line: readdata[qa]=='1' as true. in which qa is the counter I use in a for loop and readdata is a character array consisting of 50 characters that are either 0, 1 or 2.
this is the entire code:
#include <iostream> #include <fstream> #include <string> using namespace std;
[Code]....
at first is also went wrong at line 22 and also returned that as true, but then I added brackets and it worked.
I am trying to concatenate two words from a file together. ex: "joe" "bob" into "joe bob". I have provided my function(s) below. I am somehow obtaining the terminal readout below. I have initialized my memory (I have to use dynamic, dont suggest fixing that). I have set up my char arrays (I HAVE TO USE CHAR ARRAYS (c-style string) DONT SUGGEST STRINGS) I know this is a weird way to do this, but it is academic. I am currently stuck. My file will read in to my tempfName and templName and will concatenate correctly into my tempName, but I am unable to correctly get into my (*playerPtr).name.
/* this is my terminal readout joe bob <- nothing is put into (*playerPtr).name, why not? joe bob joe bob seg fault*/ /****************************************************************/ //This is here to show my struct/playerInit
I wrote this simplified version of a program i am writing that parses data in UDP packets. In the process of doing so i pretty much answered all my questions and fix all the problems i was having.
decodeSystemMap function will be in loop, and will proccess packets that have mostly the same data, only a few items will be added or changed or deleted.
whats the best way to check if there are any new, deleted, or removed items in the packet and only modify those? Is there anything unsafe / dangrous about the way the code is now?
Code: /* * File: main.c * Author: david * * Created on May 23, 2013, 11:57 AM */
