Search Results

Search found 4688 results on 188 pages for 'io redirection'.

Page 42/188 | < Previous Page | 38 39 40 41 42 43 44 45 46 47 48 49  | Next Page >

  • File Operations in Android NDK

    - by EnderX
    I am using the Android NDK to make an application primarily in C for performance reasons, but it appears that file operations such as fopen do not work correctly in Android. Whenever I try to use these functions, the application crashes. How do I create/write to a file with the Android NDK?

    Read the article

  • Using scanf() in C++ programs is faster than using cin ?

    - by zeroDivisible
    Hello, I don't know if this is true, but when I was reading FAQ on one of the problem providing sites, I found something, that poke my attention: Check your input/output methods. In C++, using cin and cout is too slow. Use these, and you will guarantee not being able to solve any problem with a decent amount of input or output. Use printf and scanf instead. Can someone please clarify this? Is really using scanf() in C++ programs faster than using cin something ? If yes, that is it a good practice to use it in C++ programs? I thought that it was C specific, though I am just learning C++...

    Read the article

  • Saving MP3 playlist to file

    - by Northernen
    Hello. I am making my own crude MP3 player, and I now have a JList with which I have populated a number of files in the form of MP3 objects (displayed on frame using DefaultListModel). I would now like to have the oppurtunity to save this JList to a file on disk. How would I go about doing this? I'm very new with programming and Java, so help is greatly appreciated.

    Read the article

  • Read whole ASCII file into C++ std::string

    - by Arrieta
    Hello, I need to read a whole file into memory and place it in a C++ std::string. If I were to read it into a char, the answer would be very simple: std::ifstream t; int lenght; t.open("file.txt", "r"); // open input file t.seekg(0, std::ios::end); // go to the end length = t.tellg(); // report location (this is the lenght) t.seekg(0, std::ios::beg); // go back to the beginning buffer = new char[length]; // allocate memory for a buffer of appropriate dimension t.read(buffer, length); // read the whole file into the buffer t.close(); // close file handle // ... do stuff with buffer here ... Now, I want to do the exact same thing, but using a std::string instead of a char. I want to avoid loops, i. e., I don't want to: std::ifstream t; t.open("file.txt", "r"); std::string buffer; std::string line; while(t){ std::getline(t, line); // ... append line to buffer and go on } t.close() any ideas?

    Read the article

  • How to delete duplicate/aggregate rows faster in a file using Java (no DB)

    - by S. Singh
    I have a 2GB big text file, it has 5 columns delimited by tab. A row will be called duplicate only if 4 out of 5 columns matches. Right now, I am doing dduping by first loading each coloumn in separate List , then iterating through lists, deleting the duplicate rows as it encountered and aggregating. The problem: it is taking more than 20 hours to process one file. I have 25 such files to process. Can anyone please share their experience, how they would go about doing such dduping? This dduping will be a throw away code. So, I was looking for some quick/dirty solution, to get job done as soon as possible. Here is my pseudo code (roughly) Iterate over the rows i=current_row_no. Iterate over the row no. i+1 to last_row if(col1 matches //find duplicate && col2 matches && col3 matches && col4 matches) { col5List.set(i,get col5); //aggregate } Duplicate example A and B will be duplicate A=(1,1,1,1,1), B=(1,1,1,1,2), C=(2,1,1,1,1) and output would be A=(1,1,1,1,1+2) C=(2,1,1,1,1) [notice that B has been kicked out]

    Read the article

  • Program crashes after trying to use a recently created file. C#

    - by Jason T.
    So here is my code if (!File.Exists(pathName)) { File.Create(pathName); } StreamWriter outputFile = new StreamWriter(pathName,true); But whenever I run the program the first time the path with file gets created. However once I get to the StreamWriter line my program crashes because it says my fie is in use by another process. Is there something I'm missing between the File.Create and the StreamWriter statements?

    Read the article

  • Improve performance writing 10 million records to text file using windows service

    - by user1039583
    I'm fetching more than 10 millions of records from database and writing to a text file. It takes hours of time to complete this operation. Is there any option to use TPL features here? It would be great if someone could get me started implementing this with the TPL. using (FileStream fStream = new FileStream("d:\\file.txt", FileMode.OpenOrCreate, FileAccess.ReadWrite)) { BufferedStream bStream = new BufferedStream(fStream); TextWriter writer = new StreamWriter(bStream); for (int i = 0; i < 100000000; i++) { writer.WriteLine(i); } bStream.Flush(); writer.Flush(); // empty buffer; fStream.Flush(); }

    Read the article

  • RAKE won'tt create xml file

    - by user296507
    hi, i'm a bit lost here as to why my RAKE task will not create the desired XML file, however it works fine when i have the method 'build_xml' in the .RB file. require 'rubygems' require 'nokogiri' require 'open-uri' namespace :xml do desc "xml build test" task :xml_build => :environment do build_xml end end def build_xml #build xml docoument builder = Nokogiri::XML::Builder.new do |xml| xml.root { xml.location { xml.value "test" } } end File.open("test.xml", 'w') {|f| f.write(builder.to_xml) } end

    Read the article

  • Read a file with 2048 bytes

    - by Suresh S
    Guys i have a file which has only one line. The file has no encoding it is a simple text file with single line. For every 2048 byte in a line , there is new record of 151 byte (totally 13*151 byte = 1945 records + 85 byte empty space). similarly for the next 2048 bytes. What is the best file i/o to use? i am thinking of reading 2048 bytes from file and storing it in an array . while (offset < fileLength &&(numRead=in.read(recordChunks, offset,alength)) >= 0) { } how can i get from the read statement only 2048 bytes at a time . i am getting IndexOutofBoundException.

    Read the article

  • best practices question: How to save a collection of images and a java object in a single file? File

    - by Richard
    Hi all, I am making a java program that has a collection of flash-card like objects. I store the objects in a jtree composed of defaultmutabletreenodes. Each node has a user object attached to it with has a few string/native data type parameters. However, i also want each of these objects to have an image (typical formats, jpg, png etc). I would like to be able to store all of this information, including the images and the tree data to the disk in a single file so the file can be transferred between users and the entire tree, including the images and parameters for each object, can be reconstructed. I had not approached a problem like this before so I was not sure what the best practices were. I found XLMEncoder (http://java.sun.com/j2se/1.4.2/docs/api/java/beans/XMLEncoder.html) to be a very effective way of storing my tree and the native data type information. However I couldn't figure out how to save the image data itself inside of the XML file, and I'm not sure it is possible since the data is binary (so restricted characters would be invalid). My next thought was to associate a hash string instead of an image within each user object, and then gzip together all of the images, with the hash strings as the names and the XMLencoded tree in the same compmressed file. That seemed really contrived though. Does anyone know a good approach for this type of issue? THanks! Thanks!

    Read the article

  • Windows equivalent of inb(), outb(), low level i/o

    - by Sebastian Dwornik
    I have some Linux code that monitors our hardware by collecting temperatures, voltages, and fan speeds, from the motherboard using inb(), outb(), inl(), etc. low level i/o functions. My challenge is to port that code over to run under Windows as a simple console app. But am puzzled in what functions Win32 (or .NET) provide that allow me permission to access direct memory mapped ports. I don't want to code a system driver either. My Windows tool preference is VS2008. (fyi) Is this possible?

    Read the article

  • Add up values from a text file

    - by Stanley
    Hi Guys I have a text file that contains Amounts at Substring (34, 47) of each line. I need to sum Up all the Values to the End of the File. I have this code that I had started to build but I do not know how to proceed from here: public class Addup { /** * @param args the command line arguments */ public static void main(String[] args) throws FileNotFoundException, IOException { // TODO code application logic here FileInputStream fs = new FileInputStream("C:/Analysis/RL004.TXT"); BufferedReader br = new BufferedReader(new InputStreamReader(fs)); String line; while((line = br.readLine()) != null){ String num = line.substring(34, 47); double i = Double.parseDouble(num); System.out.println(i); } } } The output is like this: 1.44576457E4 2.33434354E6 4.56875685E3 The Amount is in two decimal Places and I need the result also in the Two decimal Places. What Is the Best way to achieve this?

    Read the article

  • how to write floating value accurately to a bin file.

    - by user319873
    Hi I am trying to dump the floating point values from my program to a bin file. Since I can't use any stdlib function, I am thinking of writting it char by char to a big char array which I am dumping in my test application to a file. It's like float a=3132.000001; I will be dumping this to a char array in 4 bytes. Code example would be:- if((a < 1.0) && (a > 1.0) || (a > -1.0 && a < 0.0)) a = a*1000000 // 6 bit fraction part. Can you please help me writting this in a better way.

    Read the article

  • Python f.write() at beginning of file?

    - by kristus
    I'm doing it like this now, but i want it to write at the beginning of the file instead. f = open('out.txt', 'a') # or 'w'? f.write("string 1") f.write("string 2") f.write("string 3") f.close() so that the contenst of out.txt will be: string 3 string 2 string 1 and not (like this code does): string 1 string 2 string 3

    Read the article

  • Can I set a timeout for a InputStream's read() function?

    - by Zombies
    I have a DataInputStream that I obtained from a Socket. Is there any way I can set a timeout for dis.read(...)? Currently I spawn a new thread to do the read. While the parent thread does a thread.join(timeout) to wait before interrupting it. I am aware of nio, but I don't think I want to refactor that much at this point. Thanks.

    Read the article

  • Changing brightness in bufferedImage with DataBufferInt

    - by user2958025
    I must read some image and then I have to change brightness and contrast of this image I create main class and constructor where are panels, sliders and other stuff, I added changeListener to slider to take current value. My imagePanel is new Object of that class: public class Obrazek extends JPanel{ public static BufferedImage img = null; public Obrazek() { super(); try { img = ImageIO.read(new File("D:\\ja.jpg")); } catch (IOException e) {} } @Override public void paint(Graphics g) { g.drawImage(img, 0, 0, null); } } This is my load button private void przyciskWczytaj(java.awt.event.ActionEvent evt) { int odpowiedz = jFileChooser1.showOpenDialog(this); if (odpowiedz == jFileChooser1.APPROVE_OPTION) { File file = jFileChooser1.getSelectedFile(); try { BufferedImage im = ImageIO.read(new File(file.getAbsolutePath())); Obrazek.img = im; } catch (IOException ex) { System.out.println("Error"); } } } And now I want to create class where I will change that brightness. I have to use but I don't know how to use that thing: BufferedImage(256, 256, Bufferedmage.TYPE_INT_RGB) and to get each pixel of image I need to do something like: int rgb []=((DataBufferInt)img.getRaster().getDataBuffer()).getData(); And here I is next problem: How can I change the value of each r,g,b and show that new image on my panel

    Read the article

  • [NSData dataWithContentsOfFile:path] doesn't work

    - by Felics
    Hello, when I have the fallowing code to read a binary file: NSString* file = [NSString stringWithUTF8String:fileName]; NSString* filePath = resource ? [[NSBundle mainBundle] pathForResource:file ofType:nil] : [[NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex:0] stringByAppendingPathComponent: file]; NSData* fileData = [NSData dataWithContentsOfFile:filePath]; Where "fileName" and resource are load function parameters. "resource" is used to know if the file is located in application bundle or in Documents. Sometimes this code works well and sometimes it doesn't. As far I saw this problem is random. I can run the code 10 times in a row and it works fine and after that it gives me nil data without any modification. Does anybody knows what could be the problem? Could it be related with file extension or file name? Thank you. PS: I use this code on iPhone Simulator and the file exists in application bundle.

    Read the article

  • StreamReader not working as expected

    - by Jon Preece
    Hi, I have written a simple utility that loops through all C# files in my project and updates the copyright text at the top. For example, a file may look like this; //Copyright My Company, © 2009-2010 The program should update the text to look like this; //Copyright My Company, © 2009-2010 However, the code I have written results in this; //Copyright My Company, � 2009-2011 Here is the code I am using; public bool ModifyFile(string filePath, List<string> targetText, string replacementText) { if (!File.Exists(filePath)) return false; if (targetText == null || targetText.Count == 0) return false; if (string.IsNullOrEmpty(replacementText)) return false; string modifiedFileContent = string.Empty; bool hasContentChanged = false; //Read in the file content using (StreamReader reader = File.OpenText(filePath)) { string file = reader.ReadToEnd(); //Replace any target text with the replacement text foreach (string text in targetText) modifiedFileContent = file.Replace(text, replacementText); if (!file.Equals(modifiedFileContent)) hasContentChanged = true; } //If we haven't modified the file, dont bother saving it if (!hasContentChanged) return false; //Write the modifications back to the file using (StreamWriter writer = new StreamWriter(filePath)) { writer.Write(modifiedFileContent); } return true; } Any help/suggestions are appreciated. Thanks!

    Read the article

  • How to run a set of SQL queries from a file, in PHP?

    - by Harish Kurup
    I have some set of SQL queries which is in a file(i.e query.sql), and i want to run those queries in files using PHP, the code that i have wrote is not working, //database config's... $file_name="query.sql"; $query==file($file_name); $array_length=count($query); for($i=0;$i<$array_length;$i++) { $data .= $query[$i]; } echo $data; mysql_query($data); it echos the SQL Query from the file but throws an error at mysql_query() function...

    Read the article

  • Best directory to store application data with read\write rights for all users?

    - by Wodzu
    Hi guys. Until Windows Vista I was saving my application data into the directory where the program was located. The most common place was "C:\Program Files\MyApplication". As we know, under Vista and later the common user does't have rights to write under "Program Files" folder. So my first idea was to save the application data under "All Useres\Application Data" folder. But it seams that this folder has writing restrictions too! So to sum up, my requirements are: Folder should exist under Windows XP and above Microsoft's systems. All useres of the system should read\write\creation rights to this folder and it subfolders and files. I want to have only one copy of file\files for all useres. Thanks for your time.

    Read the article

  • Scanner's Read Line returning NoSuchElementException

    - by Brian
    This is my first time using StackOverflow. I am trying to read a text file which consists of a single number one the first line. try { Scanner s = new Scanner(new File("HighScores.txt")); int temp =Integer.parseInt(s.nextLine()); s.close(); return temp; } catch (FileNotFoundException e) { // TODO Auto-generated catch block e.printStackTrace(); } However, I get an error: java.util.NoSuchElementException: No line found at java.util.Scanner.nextLine(Unknown Source) at GameStart.getHighScore(GameStart.java:334) at GameStart.init(GameStart.java:82) at sun.applet.AppletPanel.run(Unknown Source) at java.lang.Thread.run(Unknown Source) I know that HighScores.txt is not empty, so why is this problem occuring? I tried using BufferedReader, and BufferReader.readLine() return null.

    Read the article

< Previous Page | 38 39 40 41 42 43 44 45 46 47 48 49  | Next Page >