Search Results

Search found 48797 results on 1952 pages for 'read write'.

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

Page 115/1952 | < Previous Page | 111 112 113 114 115 116 117 118 119 120 121 122  | Next Page >

  • 45 Different Services, Sites, and Apps to Help You Read Your Favorite Sites (Like How-To Geek)

    - by Eric Z Goodnight
    Ever wonder how geeks stay connected with their favorite blogs and writers? Read on to learn about RSS feeds and how easy they are to use with these 45 apps, services, and websites that can help you stay current. Note: of course, our more geeky readers are going to understand a lot of this already, which is why we included 45 great services that you might not have heard about before. Keep reading for more, or give you advice to the newbies in the comments Latest Features How-To Geek ETC HTG Projects: How to Create Your Own Custom Papercraft Toy How to Combine Rescue Disks to Create the Ultimate Windows Repair Disk What is Camera Raw, and Why Would a Professional Prefer it to JPG? The How-To Geek Guide to Audio Editing: The Basics How To Boot 10 Different Live CDs From 1 USB Flash Drive The 20 Best How-To Geek Linux Articles of 2010 Lord of the Rings Movie Parody Double Feature [Video] Turn a Webpage into an Asteroids-Styled Shooting Game in Opera Dolphin Browser Mini Leaves Beta; Sports New GUI, Easy Bookmarking, and More Updated Google Goggles Scans Faster; Solves Sudoku Puzzles Snowy Castle Retreat in the Mountains Wallpaper Fix TV Show Sorting Issues on iOS Devices

    Read the article

  • How to read reduce/shift conflicts in LR(1) DFA?

    - by greenoldman
    I am reading an explanation (awesome "Parsing Techniques" by D.Grune and C.J.H.Jacobs; p.293 in the 2nd edition) and I moved forward from my last question: How to get lookahead symbol when constructing LR(1) NFA for parser? Now I have such "problem" (maybe not a problem, but rather need of confirmation from some more knowledgeable people). The authors present state in LR(0) which has reduce/shift conflict. Then they build DFA for LR(1) for the same grammar. And now they say it does not have a conflict (lookaheads at the end): S -> E . eof E -> E . - T eof E -> E . - T - and there is an edge from this state labeled - but no labeled eof. Authors says, that on eof there will be reduce, on - there will be shift. However eof is for shift as well (as lookahead). So my personal understanding of LR(1) DFA is this -- you can drop lookaheads for shifts, because they serve no purpose now -- shifts rely on input, not on lookaheads -- and after that, remove duplicates. S -> E . eof E -> E . - T So the lookahead for reduce serves as input really, because at this stage (all required input is read) it is really incoming symbol right now. For shifts, the input symbols are on the edges. So my question is this -- am I actually right about dropping lookaheads for shifts (after fully constructing DFA)?

    Read the article

  • Writing Strings to files in python

    - by Leif Andersen
    I'm getting the following error when trying to write a string to a file in pythion: Traceback (most recent call last): File "export_off.py", line 264, in execute save_off(self.properties.path, context) File "export_off.py", line 244, in save_off primary.write(file) File "export_off.py", line 181, in write variable.write(file) File "export_off.py", line 118, in write file.write(self.value) TypeError: must be bytes or buffer, not str I basically have a string class, which contains a string: class _off_str(object): __slots__ = 'value' def __init__(self, val=""): self.value=val def get_size(self): return SZ_SHORT def write(self,file): file.write(self.value) def __str__(self): return str(self.value) Furthermore, I'm calling that class like this: def write(self, file): for variable in self.variables: variable.write(file) I have no idea what is going on. I've seen other python programs writing strings to files, so why can't this one? Thank you very much for your help.

    Read the article

  • Bundler isn't loading gems

    - by Garrett
    I have been having a problem with using Bundler and being able to access my gems without having to require them somewhere, as config.gem used to do that for me (as far as I know). In my Rails 3 app, I defined my Gemfile like so: clear_sources source "http://gemcutter.org" source "http://gems.github.com" bundle_path "vendor/bundler_gems" ## Bundle edge rails: git "git://github.com/rails/arel.git" git "git://github.com/rails/rack.git" gem "rails", :git => "git://github.com/rails/rails.git" ## Bundle gem "mongo_mapper", :git => "git://github.com/jnunemaker/mongomapper.git" gem "bluecloth", ">= 2.0.0" Then I run gem bundle, it bundles it all up like expected. Inside the environment.rb file that is included within boot.rb it looks like this: # DO NOT MODIFY THIS FILE module Bundler file = File.expand_path(__FILE__) dir = File.dirname(file) ENV["PATH"] = "#{dir}/../../../../bin:#{ENV["PATH"]}" ENV["RUBYOPT"] = "-r#{file} #{ENV["RUBYOPT"]}" $LOAD_PATH.unshift File.expand_path("#{dir}/gems/builder-2.1.2/bin") $LOAD_PATH.unshift File.expand_path("#{dir}/gems/builder-2.1.2/lib") $LOAD_PATH.unshift File.expand_path("#{dir}/gems/text-hyphen-1.0.0/bin") $LOAD_PATH.unshift File.expand_path("#{dir}/gems/text-hyphen-1.0.0/lib") $LOAD_PATH.unshift File.expand_path("#{dir}/gems/i18n-0.3.3/bin") $LOAD_PATH.unshift File.expand_path("#{dir}/gems/i18n-0.3.3/lib") $LOAD_PATH.unshift File.expand_path("#{dir}/dirs/arel/bin") $LOAD_PATH.unshift File.expand_path("#{dir}/dirs/arel/lib") $LOAD_PATH.unshift File.expand_path("#{dir}/dirs/rails/activemodel/bin") $LOAD_PATH.unshift File.expand_path("#{dir}/dirs/rails/activemodel/lib") $LOAD_PATH.unshift File.expand_path("#{dir}/gems/jnunemaker-validatable-1.8.1/bin") $LOAD_PATH.unshift File.expand_path("#{dir}/gems/jnunemaker-validatable-1.8.1/lib") $LOAD_PATH.unshift File.expand_path("#{dir}/gems/abstract-1.0.0/bin") $LOAD_PATH.unshift File.expand_path("#{dir}/gems/abstract-1.0.0/lib") $LOAD_PATH.unshift File.expand_path("#{dir}/gems/erubis-2.6.5/bin") $LOAD_PATH.unshift File.expand_path("#{dir}/gems/erubis-2.6.5/lib") $LOAD_PATH.unshift File.expand_path("#{dir}/gems/mime-types-1.16/bin") $LOAD_PATH.unshift File.expand_path("#{dir}/gems/mime-types-1.16/lib") $LOAD_PATH.unshift File.expand_path("#{dir}/gems/mail-2.1.2/bin") $LOAD_PATH.unshift File.expand_path("#{dir}/gems/mail-2.1.2/lib") $LOAD_PATH.unshift File.expand_path("#{dir}/gems/rake-0.8.7/bin") $LOAD_PATH.unshift File.expand_path("#{dir}/gems/rake-0.8.7/lib") $LOAD_PATH.unshift File.expand_path("#{dir}/dirs/rails/railties/bin") $LOAD_PATH.unshift File.expand_path("#{dir}/dirs/rails/railties/lib") $LOAD_PATH.unshift File.expand_path("#{dir}/gems/memcache-client-1.7.7/bin") $LOAD_PATH.unshift File.expand_path("#{dir}/gems/memcache-client-1.7.7/lib") $LOAD_PATH.unshift File.expand_path("#{dir}/dirs/rack/bin") $LOAD_PATH.unshift File.expand_path("#{dir}/dirs/rack/lib") $LOAD_PATH.unshift File.expand_path("#{dir}/gems/rack-test-0.5.3/bin") $LOAD_PATH.unshift File.expand_path("#{dir}/gems/rack-test-0.5.3/lib") $LOAD_PATH.unshift File.expand_path("#{dir}/gems/rack-mount-0.4.5/bin") $LOAD_PATH.unshift File.expand_path("#{dir}/gems/rack-mount-0.4.5/lib") $LOAD_PATH.unshift File.expand_path("#{dir}/dirs/rails/actionpack/bin") $LOAD_PATH.unshift File.expand_path("#{dir}/dirs/rails/actionpack/lib") $LOAD_PATH.unshift File.expand_path("#{dir}/gems/bluecloth-2.0.7/bin") $LOAD_PATH.unshift File.expand_path("#{dir}/gems/bluecloth-2.0.7/lib") $LOAD_PATH.unshift File.expand_path("#{dir}/gems/bluecloth-2.0.7/ext") $LOAD_PATH.unshift File.expand_path("#{dir}/dirs/rails/activerecord/bin") $LOAD_PATH.unshift File.expand_path("#{dir}/dirs/rails/activerecord/lib") $LOAD_PATH.unshift File.expand_path("#{dir}/gems/text-format-1.0.0/bin") $LOAD_PATH.unshift File.expand_path("#{dir}/gems/text-format-1.0.0/lib") $LOAD_PATH.unshift File.expand_path("#{dir}/dirs/rails/actionmailer/bin") $LOAD_PATH.unshift File.expand_path("#{dir}/dirs/rails/actionmailer/lib") $LOAD_PATH.unshift File.expand_path("#{dir}/gems/tzinfo-0.3.16/bin") $LOAD_PATH.unshift File.expand_path("#{dir}/gems/tzinfo-0.3.16/lib") $LOAD_PATH.unshift File.expand_path("#{dir}/dirs/rails/activesupport/bin") $LOAD_PATH.unshift File.expand_path("#{dir}/dirs/rails/activesupport/lib") $LOAD_PATH.unshift File.expand_path("#{dir}/dirs/rails/activeresource/bin") $LOAD_PATH.unshift File.expand_path("#{dir}/dirs/rails/activeresource/lib") $LOAD_PATH.unshift File.expand_path("#{dir}/dirs/rails/bin") $LOAD_PATH.unshift File.expand_path("#{dir}/dirs/rails/lib") $LOAD_PATH.unshift File.expand_path("#{dir}/gems/mongo-0.18.2/bin") $LOAD_PATH.unshift File.expand_path("#{dir}/gems/mongo-0.18.2/lib") $LOAD_PATH.unshift File.expand_path("#{dir}/dirs/mongomapper/bin") $LOAD_PATH.unshift File.expand_path("#{dir}/dirs/mongomapper/lib") @gemfile = "#{dir}/../../../../Gemfile" require "rubygems" unless respond_to?(:gem) # 1.9 already has RubyGems loaded @bundled_specs = {} @bundled_specs["builder"] = eval(File.read("#{dir}/specifications/builder-2.1.2.gemspec")) @bundled_specs["builder"].loaded_from = "#{dir}/specifications/builder-2.1.2.gemspec" @bundled_specs["text-hyphen"] = eval(File.read("#{dir}/specifications/text-hyphen-1.0.0.gemspec")) @bundled_specs["text-hyphen"].loaded_from = "#{dir}/specifications/text-hyphen-1.0.0.gemspec" @bundled_specs["i18n"] = eval(File.read("#{dir}/specifications/i18n-0.3.3.gemspec")) @bundled_specs["i18n"].loaded_from = "#{dir}/specifications/i18n-0.3.3.gemspec" @bundled_specs["arel"] = eval(File.read("#{dir}/specifications/arel-0.2.pre.gemspec")) @bundled_specs["arel"].loaded_from = "#{dir}/specifications/arel-0.2.pre.gemspec" @bundled_specs["activemodel"] = eval(File.read("#{dir}/specifications/activemodel-3.0.pre.gemspec")) @bundled_specs["activemodel"].loaded_from = "#{dir}/specifications/activemodel-3.0.pre.gemspec" @bundled_specs["jnunemaker-validatable"] = eval(File.read("#{dir}/specifications/jnunemaker-validatable-1.8.1.gemspec")) @bundled_specs["jnunemaker-validatable"].loaded_from = "#{dir}/specifications/jnunemaker-validatable-1.8.1.gemspec" @bundled_specs["abstract"] = eval(File.read("#{dir}/specifications/abstract-1.0.0.gemspec")) @bundled_specs["abstract"].loaded_from = "#{dir}/specifications/abstract-1.0.0.gemspec" @bundled_specs["erubis"] = eval(File.read("#{dir}/specifications/erubis-2.6.5.gemspec")) @bundled_specs["erubis"].loaded_from = "#{dir}/specifications/erubis-2.6.5.gemspec" @bundled_specs["mime-types"] = eval(File.read("#{dir}/specifications/mime-types-1.16.gemspec")) @bundled_specs["mime-types"].loaded_from = "#{dir}/specifications/mime-types-1.16.gemspec" @bundled_specs["mail"] = eval(File.read("#{dir}/specifications/mail-2.1.2.gemspec")) @bundled_specs["mail"].loaded_from = "#{dir}/specifications/mail-2.1.2.gemspec" @bundled_specs["rake"] = eval(File.read("#{dir}/specifications/rake-0.8.7.gemspec")) @bundled_specs["rake"].loaded_from = "#{dir}/specifications/rake-0.8.7.gemspec" @bundled_specs["railties"] = eval(File.read("#{dir}/specifications/railties-3.0.pre.gemspec")) @bundled_specs["railties"].loaded_from = "#{dir}/specifications/railties-3.0.pre.gemspec" @bundled_specs["memcache-client"] = eval(File.read("#{dir}/specifications/memcache-client-1.7.7.gemspec")) @bundled_specs["memcache-client"].loaded_from = "#{dir}/specifications/memcache-client-1.7.7.gemspec" @bundled_specs["rack"] = eval(File.read("#{dir}/specifications/rack-1.1.0.gemspec")) @bundled_specs["rack"].loaded_from = "#{dir}/specifications/rack-1.1.0.gemspec" @bundled_specs["rack-test"] = eval(File.read("#{dir}/specifications/rack-test-0.5.3.gemspec")) @bundled_specs["rack-test"].loaded_from = "#{dir}/specifications/rack-test-0.5.3.gemspec" @bundled_specs["rack-mount"] = eval(File.read("#{dir}/specifications/rack-mount-0.4.5.gemspec")) @bundled_specs["rack-mount"].loaded_from = "#{dir}/specifications/rack-mount-0.4.5.gemspec" @bundled_specs["actionpack"] = eval(File.read("#{dir}/specifications/actionpack-3.0.pre.gemspec")) @bundled_specs["actionpack"].loaded_from = "#{dir}/specifications/actionpack-3.0.pre.gemspec" @bundled_specs["bluecloth"] = eval(File.read("#{dir}/specifications/bluecloth-2.0.7.gemspec")) @bundled_specs["bluecloth"].loaded_from = "#{dir}/specifications/bluecloth-2.0.7.gemspec" @bundled_specs["activerecord"] = eval(File.read("#{dir}/specifications/activerecord-3.0.pre.gemspec")) @bundled_specs["activerecord"].loaded_from = "#{dir}/specifications/activerecord-3.0.pre.gemspec" @bundled_specs["text-format"] = eval(File.read("#{dir}/specifications/text-format-1.0.0.gemspec")) @bundled_specs["text-format"].loaded_from = "#{dir}/specifications/text-format-1.0.0.gemspec" @bundled_specs["actionmailer"] = eval(File.read("#{dir}/specifications/actionmailer-3.0.pre.gemspec")) @bundled_specs["actionmailer"].loaded_from = "#{dir}/specifications/actionmailer-3.0.pre.gemspec" @bundled_specs["tzinfo"] = eval(File.read("#{dir}/specifications/tzinfo-0.3.16.gemspec")) @bundled_specs["tzinfo"].loaded_from = "#{dir}/specifications/tzinfo-0.3.16.gemspec" @bundled_specs["activesupport"] = eval(File.read("#{dir}/specifications/activesupport-3.0.pre.gemspec")) @bundled_specs["activesupport"].loaded_from = "#{dir}/specifications/activesupport-3.0.pre.gemspec" @bundled_specs["activeresource"] = eval(File.read("#{dir}/specifications/activeresource-3.0.pre.gemspec")) @bundled_specs["activeresource"].loaded_from = "#{dir}/specifications/activeresource-3.0.pre.gemspec" @bundled_specs["rails"] = eval(File.read("#{dir}/specifications/rails-3.0.pre.gemspec")) @bundled_specs["rails"].loaded_from = "#{dir}/specifications/rails-3.0.pre.gemspec" @bundled_specs["mongo"] = eval(File.read("#{dir}/specifications/mongo-0.18.2.gemspec")) @bundled_specs["mongo"].loaded_from = "#{dir}/specifications/mongo-0.18.2.gemspec" @bundled_specs["mongo_mapper"] = eval(File.read("#{dir}/specifications/mongo_mapper-0.6.10.gemspec")) @bundled_specs["mongo_mapper"].loaded_from = "#{dir}/specifications/mongo_mapper-0.6.10.gemspec" def self.add_specs_to_loaded_specs Gem.loaded_specs.merge! @bundled_specs end def self.add_specs_to_index @bundled_specs.each do |name, spec| Gem.source_index.add_spec spec end end add_specs_to_loaded_specs add_specs_to_index def self.require_env(env = nil) context = Class.new do def initialize(env) @env = env && env.to_s ; end def method_missing(*) ; yield if block_given? ; end def only(*env) old, @only = @only, _combine_only(env.flatten) yield @only = old end def except(*env) old, @except = @except, _combine_except(env.flatten) yield @except = old end def gem(name, *args) opt = args.last.is_a?(Hash) ? args.pop : {} only = _combine_only(opt[:only] || opt["only"]) except = _combine_except(opt[:except] || opt["except"]) files = opt[:require_as] || opt["require_as"] || name files = [files] unless files.respond_to?(:each) return unless !only || only.any? {|e| e == @env } return if except && except.any? {|e| e == @env } if files = opt[:require_as] || opt["require_as"] files = Array(files) files.each { |f| require f } else begin require name rescue LoadError # Do nothing end end yield if block_given? true end private def _combine_only(only) return @only unless only only = [only].flatten.compact.uniq.map { |o| o.to_s } only &= @only if @only only end def _combine_except(except) return @except unless except except = [except].flatten.compact.uniq.map { |o| o.to_s } except |= @except if @except except end end context.new(env && env.to_s).instance_eval(File.read(@gemfile), @gemfile, 1) end end module Gem @loaded_stacks = Hash.new { |h,k| h[k] = [] } def source_index.refresh! super Bundler.add_specs_to_index end end But when I try to access any of my gems, e.g. MongoMapper, Paperclip, Haml, etc. I get: NameError: uninitialized constant MongoMapper The same goes for any other gem. Does Bundler not include gems like the old Rails 2.0 did? Or is something messed up with my system? Any help would be appreciated, thank you!

    Read the article

  • how to write the code for this program specially in mathematica? [closed]

    - by asd
    I implemented a solution to the problem below in Mathematica, but it takes a very long time (hours) to compute f of kis or the set B for large numbers. Somebody suggested that implementing this in C++ resulted in a solution in less than 10 minutes. Would C++ be a good language to learn to solve these problems, or can my Mathematica code be improved to fix the performance issues? I don't know anything about C or C++ and it should be difficult to start to learn this languages. I prefer to improve or write new code in mathematica. Problem Description Let $f$ be an arithmetic function and A={k1,k2,...,kn} are integers in increasing order. Now I want to start with k1 and compare f(ki) with f(k1). If f(ki)f(k1), put ki as k1. Now start with ki, and compare f(kj) with f(ki), for ji. If f(kj)f(ki), put kj as ki, and repeat this procedure. At the end we will have a sub sequence B={L1,...,Lm} of A by this property: f(L(i+1))f(L(i)), for any 1<=i<=m-1 For example, let f is the divisor function of integers. Here I put some part of my code and this is just a sample and the question in my program could be more larger than these: «««««««««««««««««««««««««««««««««««« f[n_] := DivisorSigma[0, n]; g[n_] := Product[Prime[i], {i, 1, PrimePi[n]}]; k1 = g[67757] g[353] g[59] g[19] g[11] g[7] g[5]^2 6^3 2^7; k2 = g[67757] g[353] g[59] g[19] g[11] g[7] g[5] 6^5 2^7; k3 = g[67757] g[359] g[53] g[19] g[11] g[7] g[5] 6^4 2^7; k4 = g[67759] g[349] g[53] g[19] g[11] g[7] g[5] 6^5 2^6; k5 = g[67757] g[359] g[53] g[19] g[11] g[7] g[5] 6^4 2^8; k6 = g[67759] g[349] g[53] g[19] g[11] g[7] g[5]^2 6^3 2^7; k7 = g[67757] g[359] g[53] g[19] g[11] g[7] g[5] 6^5 2^6; k8 = g[67757] g[359] g[53] g[19] g[11] g[7] g[5] 6^4 2^9; k9 = g[67757] g[359] g[53] g[19] g[11] g[7] g[5]^2 6^3 2^7; k10 = g[67757] g[359] g[53] g[19] g[11] g[7] g[5] 6^5 2^7; k11 = g[67759] g[349] g[53] g[19] g[11] g[7] g[5]^2 6^4 2^6; k12 = g[67757] g[359] g[53] g[19] g[11] g[7] g[5]^2 6^3 2^8; k13 = g[67757] g[359] g[53] g[19] g[11] g[7] g[5]^2 6^4 2^6; k14 = g[67757] g[359] g[53] g[19] g[11] g[7] g[5]^2 6^3 2^9; k15 = g[67757] g[359] g[53] g[19] g[11] g[7] g[5]^2 6^4 2^7; k16 = g[67757] g[359] g[53] g[23] g[11] g[7] g[5] 6^4 2^8; k17 = g[67757] g[359] g[59] g[19] g[11] g[7] g[5] 6^4 2^7; k18 = g[67757] g[359] g[53] g[23] g[11] g[7] g[5] 6^4 2^9; k19 = g[67759] g[353] g[53] g[19] g[11] g[7] g[5] 6^4 2^6; k20 = g[67763] g[347] g[53] g[19] g[11] g[7] g[5] 6^4 2^7; k = Table[k1, k2, k3, k4, k5, k6, k7, k8, k9, k10, k11, k12, k13, k14, k15, k16, k17, k18, k19, k20]; i = 1; count = 0; For[j = i, j <= 20, j++, If[f[k[[j]]] - f[k[[i]]] > 0, i = j; Print["k",i]; count = count + 1]]; Print["count= ", count] ««««««««««««««««««««««««««««««««««««

    Read the article

  • .NET Reflector 7.2 Early Access Build 2 Released: Performance Critical

    - by Bart Read
    I've just posted a write-up of some of the performance tuning I've done to improve .NET Reflector 7.2's start-up time here: http://www.reflector.net/2011/05/net-reflector-7-start-up-time-running-out-of-gas-or-pedal-to-the-metal/ You can get the new build from the .NET Reflector homepage at http://www.reflector.net/. Please remember to give us your feedback in the forum, at http://forums.reflector.net/, using the tags #7.2 and #eap. Technorati Tags: reflector,early access,7.2

    Read the article

  • External USB attached drive works in Windows XP but not in Windows 7. How to fix?

    - by irrational John
    Earlier this week I purchased this "N52300 EZQuest Pro" external hard drive enclosure from here. I can connect the enclosure using USB 2.0 and access the files in both NTFS partitions on the MBR partitioned drive when I use either Windows XP (SP3) or Mac OS X 10.6. So it works as expected in XP & Snow Leopard. However, the enclosure does not work in Windows 7 (Home Premium) either 64-bit or 32-bit or in Ubuntu 10.04 (kernel 2.6.32-23-generic). I'm thinking this must be a Windows 7 driver problem because the enclosure works in XP & Snow Leopard. I do know that no special drivers are required to use this enclosure. It is supported using the USB mass storage drivers included with XP and OS X. It should also work fine using the mass storage support in Windows 7, no? FWIW, I have also tried using 32-bit Windows 7 on both my desktop, a Gigabyte GA-965P-DS3 with a Pentium Dual-Core E6500 @ 2.93GHz, and on my early 2008 MacBook. I see the same failure in both cases that I see with 64-bit Windows 7. So it doesn't appear to be specific to one hardware platform. I'm hoping someone out there can help me either get the enclosure to work in Windows 7 or convince me that the enclosure hardware is bad and should be RMAed. At the moment though an RMA seems pointless since this appears to be a (Windows 7) device driver problem. I have tried to track down any updates to the mass storage drivers included with Windows 7 but have so far come up empty. Heck, I can't even figure out how to place a bug report with Microsoft since apparently the grace period for Windows 7 email support is only a few months. I came across a link to some USB troubleshooting steps in another question. I haven't had a chance to look over the suggestions on that site or try them yet. Maybe tomorrow if I have time ... ;-) I'll finish up with some more details about the problem. When I connect the enclosure using USB to Windows 7 at first it appears everything worked. Windows detects the drive and installs a driver for it. Looking in Device Manager there is an entry under the Hard Drives section with the title, Hitachi HDT721010SLA360 USB Device. When you open Windows Disk Management the first time after the enclosure has been attached the drive appears as "Not initialize" and I'm prompted to initialize it. This is bogus. After all, the drive worked fine in XP so I know it has already been initialized, partitioned, and formatted. So of course I never try to initialize it "again". (It's a 1 GB drive and I don't want to lose the data on it). Except for this first time, the drive never shows up in Disk Management again unless I uninstall the Hitachi HDT721010SLA360 USB Device entry under Hard Drives, unplug, and then replug the enclosure. If I do that then the process in the previous paragraph repeats. In Ubuntu the enclosure never shows up at all at the file system level. Below are an excerpt from kern.log and an excerpt from the result of lsusb -v after attaching the enclosure. It appears that Ubuntu at first recongnizes the enclosure and is attempting to attach it, but encounters errors which prevent it from doing so. Unfortunately, I don't know whether any of this info is useful or not. excerpt from kern.log [ 2684.240015] usb 1-2: new high speed USB device using ehci_hcd and address 22 [ 2684.393618] usb 1-2: configuration #1 chosen from 1 choice [ 2684.395399] scsi17 : SCSI emulation for USB Mass Storage devices [ 2684.395570] usb-storage: device found at 22 [ 2684.395572] usb-storage: waiting for device to settle before scanning [ 2689.390412] usb-storage: device scan complete [ 2689.390894] scsi 17:0:0:0: Direct-Access Hitachi HDT721010SLA360 ST6O PQ: 0 ANSI: 4 [ 2689.392237] sd 17:0:0:0: Attached scsi generic sg7 type 0 [ 2689.395269] sd 17:0:0:0: [sde] 1953525168 512-byte logical blocks: (1.00 TB/931 GiB) [ 2689.395632] sd 17:0:0:0: [sde] Write Protect is off [ 2689.395636] sd 17:0:0:0: [sde] Mode Sense: 11 00 00 00 [ 2689.395639] sd 17:0:0:0: [sde] Assuming drive cache: write through [ 2689.412003] sd 17:0:0:0: [sde] Assuming drive cache: write through [ 2689.412009] sde: sde1 sde2 [ 2689.455759] sd 17:0:0:0: [sde] Assuming drive cache: write through [ 2689.455765] sd 17:0:0:0: [sde] Attached SCSI disk [ 2692.620017] usb 1-2: reset high speed USB device using ehci_hcd and address 22 [ 2707.740014] usb 1-2: device descriptor read/64, error -110 [ 2722.970103] usb 1-2: device descriptor read/64, error -110 [ 2723.200027] usb 1-2: reset high speed USB device using ehci_hcd and address 22 [ 2738.320019] usb 1-2: device descriptor read/64, error -110 [ 2753.550024] usb 1-2: device descriptor read/64, error -110 [ 2753.780020] usb 1-2: reset high speed USB device using ehci_hcd and address 22 [ 2758.810147] usb 1-2: device descriptor read/8, error -110 [ 2763.940142] usb 1-2: device descriptor read/8, error -110 [ 2764.170014] usb 1-2: reset high speed USB device using ehci_hcd and address 22 [ 2769.200141] usb 1-2: device descriptor read/8, error -110 [ 2774.330137] usb 1-2: device descriptor read/8, error -110 [ 2774.440069] usb 1-2: USB disconnect, address 22 [ 2774.440503] sd 17:0:0:0: Device offlined - not ready after error recovery [ 2774.590023] usb 1-2: new high speed USB device using ehci_hcd and address 23 [ 2789.710020] usb 1-2: device descriptor read/64, error -110 [ 2804.940020] usb 1-2: device descriptor read/64, error -110 [ 2805.170026] usb 1-2: new high speed USB device using ehci_hcd and address 24 [ 2820.290019] usb 1-2: device descriptor read/64, error -110 [ 2835.520027] usb 1-2: device descriptor read/64, error -110 [ 2835.750018] usb 1-2: new high speed USB device using ehci_hcd and address 25 [ 2840.780085] usb 1-2: device descriptor read/8, error -110 [ 2845.910079] usb 1-2: device descriptor read/8, error -110 [ 2846.140023] usb 1-2: new high speed USB device using ehci_hcd and address 26 [ 2851.170112] usb 1-2: device descriptor read/8, error -110 [ 2856.300077] usb 1-2: device descriptor read/8, error -110 [ 2856.410027] hub 1-0:1.0: unable to enumerate USB device on port 2 [ 2856.730033] usb 3-2: new full speed USB device using uhci_hcd and address 11 [ 2871.850017] usb 3-2: device descriptor read/64, error -110 [ 2887.080014] usb 3-2: device descriptor read/64, error -110 [ 2887.310011] usb 3-2: new full speed USB device using uhci_hcd and address 12 [ 2902.430021] usb 3-2: device descriptor read/64, error -110 [ 2917.660013] usb 3-2: device descriptor read/64, error -110 [ 2917.890016] usb 3-2: new full speed USB device using uhci_hcd and address 13 [ 2922.911623] usb 3-2: device descriptor read/8, error -110 [ 2928.051753] usb 3-2: device descriptor read/8, error -110 [ 2928.280013] usb 3-2: new full speed USB device using uhci_hcd and address 14 [ 2933.301876] usb 3-2: device descriptor read/8, error -110 [ 2938.431993] usb 3-2: device descriptor read/8, error -110 [ 2938.540073] hub 3-0:1.0: unable to enumerate USB device on port 2 excerpt from lsusb -v Bus 001 Device 017: ID 0dc4:0000 Macpower Peripherals, Ltd Device Descriptor: bLength 18 bDescriptorType 1 bcdUSB 2.00 bDeviceClass 0 (Defined at Interface level) bDeviceSubClass 0 bDeviceProtocol 0 bMaxPacketSize0 64 idVendor 0x0dc4 Macpower Peripherals, Ltd idProduct 0x0000 bcdDevice 0.01 iManufacturer 1 EZ QUEST iProduct 2 USB Mass Storage iSerial 3 220417 bNumConfigurations 1 Configuration Descriptor: bLength 9 bDescriptorType 2 wTotalLength 32 bNumInterfaces 1 bConfigurationValue 1 iConfiguration 5 Config0 bmAttributes 0xc0 Self Powered MaxPower 0mA Interface Descriptor: bLength 9 bDescriptorType 4 bInterfaceNumber 0 bAlternateSetting 0 bNumEndpoints 2 bInterfaceClass 8 Mass Storage bInterfaceSubClass 6 SCSI bInterfaceProtocol 80 Bulk (Zip) iInterface 4 Interface0 Endpoint Descriptor: bLength 7 bDescriptorType 5 bEndpointAddress 0x01 EP 1 OUT bmAttributes 2 Transfer Type Bulk Synch Type None Usage Type Data wMaxPacketSize 0x0200 1x 512 bytes bInterval 0 Endpoint Descriptor: bLength 7 bDescriptorType 5 bEndpointAddress 0x81 EP 1 IN bmAttributes 2 Transfer Type Bulk Synch Type None Usage Type Data wMaxPacketSize 0x0200 1x 512 bytes bInterval 0 Device Qualifier (for other device speed): bLength 10 bDescriptorType 6 bcdUSB 2.00 bDeviceClass 0 (Defined at Interface level) bDeviceSubClass 0 bDeviceProtocol 0 bMaxPacketSize0 64 bNumConfigurations 1 Device Status: 0x0001 Self Powered Update: Results using Firewire to connect. Today I recieved a 1394b 9 pin to 1394a 6 pin cable which allowed me to connect the "EZQuest Pro" via Firewire. Everything works. When I use Firewire I can connect whether I'm using Windows 7 or Ubuntu 10.04. I even tried booting my Gigabyte desktop as an OS X 10.6.3 Hackintosh and it worked there as well. (Though if I recall correctly, it also worked when using USB 2.0 and booting OS X on the desktop. Certainly it works with USB 2.0 and my MacBook.) I believe the firmware on the device is at the latest level available, v1.07. I base this on the excerpt below from the OS X System Profiler which shows Firmware Revision: 0x107. Bottom line: It's nice that the enclosure is actually usable when I connect with Firewire. But I am still searching for an answer as to why it does not work correctly when using USB 2.0 in Windows 7 (and Ubuntu ... but really Windows 7 is my biggest concern). OXFORD IDE Device 1: Manufacturer: EZ QUEST Model: 0x0 GUID: 0x1D202E0220417 Maximum Speed: Up to 800 Mb/sec Connection Speed: Up to 400 Mb/sec Sub-units: OXFORD IDE Device 1 Unit: Unit Software Version: 0x10483 Unit Spec ID: 0x609E Firmware Revision: 0x107 Product Revision Level: ST6O Sub-units: OXFORD IDE Device 1 SBP-LUN: Capacity: 1 TB (1,000,204,886,016 bytes) Removable Media: Yes BSD Name: disk3 Partition Map Type: MBR (Master Boot Record) S.M.A.R.T. status: Not Supported

    Read the article

  • Is there an easy way to transfer PDF, Mobi, epub, ebooks to the iPad to read yet?

    - by Jian Lin
    Besides the 2 ways by using email or putting the PDF on a website (but it is a trouble to go to page 180 by repeated scrolling), is there an easy way to transfer the .PDF, .mobi, .epub to iPad to read, preferably to Kindle or iBooks on the iPad, so that we can add notes or hightlight or bookmark the pages? There seems to be way even on the O'Reilly page but it doesn't seem to work: http://oreilly.com/ebooks/mobi/ http://answers.oreilly.com/topic/1293-how-to-read-oreilly-ebooks-on-the-ipad-that-arent-from-the-ibooks-store/

    Read the article

  • Does software RAID 1 in Windows 7 improve read speeds?

    - by Rich
    As the title says, does software RAID 1 (mirroring) in Windows 7 improve read speeds? I'd like to set up RAID 1 to help protect my important documents (yes, yes, I know it's not a backup), but performance is also important to me. As I understand it, RAID 1 should theoretically be able to improve my read speeds by n times, where n is the number of disks. Is Windows 7 able to get this boost? I haven't been able to find out this information anywhere.

    Read the article

  • How can I read password protected Word files on OS X ?

    - by Ohad
    I receive Word documents by mail and read them using the built-in Gmail reader. Sometimes the documents are password protected and I need to obtain access to a Windows machine with Office installed in order to read them. Is there a quicker / less hassle requiring method ? I don't want to have to install Vmware / Parallels nor Office on my fresh and sterile macbook.

    Read the article

  • What is the most secure way to allow a user read access to a log file?

    - by gAMBOOKa
    My application requires read access to /var/log/messages, which belongs to user and group root. What is the minimal exposure level required on /var/log/messages so my application can read it? Presently, my plan is to change the group ownership of /var/log/messages to a new group, and add root and my application user to it, but this would also give the application write privileges to /var/log/messages. OS: Centos 5.5

    Read the article

  • How to read external USB hard drive formatted ext3 from Windows 7?

    - by CChriss
    I had to format a USB hard drive to ext3 to use it with a Linksys nas box. Now I can't read the hd when I unplug it from the nas and plug it directly into my Windows 7 computer. (The computer accesses the nas over a wireless connection, so I like to plug the hd directly into my pc when transferring large files.) How can I leave the hd formatted with ext3 and yet be able to access it (read/write) when I plug it directly into my pc?

    Read the article

  • Does chunk size affect the read performance of a Linux md software RAID1 array?

    - by OldWolf
    This came up in relation to this question on determining chunk size of an existing RAID array. The general consensus seems to be that chunk size does not apply to RAID1 as it is not striped. On the other hand, the Linux RAID Wiki claims that it will have an affect on read performance. However, I cannot find any benchmarks testing/proving that. Can anyone point to conclusive documentation that it either does or does not affect read performance?

    Read the article

  • why are read only form fields in django a bad idea?

    - by jamida
    I've been looking for a way to create a read-only form field and every article I've found on the subject comes with a statement that "this is a bad idea". Now for an individual form, I can understand that there are other ways to solve the problem, but using a read only form field in a modelformset seems like a completely natural idea. Consider a teacher grade book application where the teacher would like to be able to enter all the students' (note the plural students) grades with a single SUBMIT. A modelformset could iterate over all the student-grades in such a way that the student name is read-only and the grade is the editable field. I like the power and convenience of the error checking and error reporting you get with a modelformset but leaving the student name editable in such a formset is crazy. Since the expert django consensus is that read-only form fields are a bad idea, I was wondering what the standard django best practice is for the example student-grade example above?

    Read the article

  • Can Sql Server BULK INSERT read from a named pipe/fifo?

    - by Peter
    Is it possible for BULK INSERT/bcp to read from a named pipe, fifo-style? That is, rather than reading from a real text file, can BULK INSERT/bcp be made to read from a named pipe which is on the write end of another process? For example: create named pipe unzip file to named pipe read from named pipe with bcp or BULK INSERT or: create 4 named pipes split 1 file into 4 streams, writing each stream to a separate named pipe read from 4 named pipes into 4 tables w/ bcp or BULK INSERT The closest I've found was this fellow (site now unreachable), who managed to write to a named pipe w/ bcp, with a his own utility and usage like so: start /MIN ZipPipe authors_pipe authors.txt.gz 9 bcp pubs..authors out \\.\pipe\authors_pipe -T -n But he couldn't get the reverse to work. So before I head off on a fool's errand, I'm wondering whether it's fundamentally possible to read from a named pipe w/ BULK INSERT or bcp. And if it is possible, how would one set it up? Would NamedPipeServerStream or something else in the .NET System.IO.Pipes namespace be adequate? eg, an example using Powershell: [reflection.Assembly]::LoadWithPartialName("system.core") $pipe = New-Object system.IO.Pipes.NamedPipeServerStream("Bob") And then....what?

    Read the article

  • panic! apache2 cannot start due to unable to read error.log !

    - by vvvvvvv
    apache2 fails to start because it cannot open error.log I've checked the syslog, and found something troubling... Jan 20 02:58:18 unassigned sm-mta[3559]: o0FAD04C017861: to=<[email protected]>, delay=4+22:45:18, xdelay=00:06:18, mailer=esmtp, pri=63390823, relay=asdfa$ Jan 20 03:00:01 unassigned /USR/SBIN/CRON[3939]: (root) CMD (if [ -x /usr/bin/vnstat ] && [ `ls /var/lib/vnstat/ | wc -l` -ge 1 ]; then /usr/bin/vnstat -u; f$ Jan 20 03:00:01 unassigned /USR/SBIN/CRON[3944]: (smmsp) CMD (test -x /etc/init.d/sendmail && /usr/share/sendmail/sendmail cron-msp) Jan 20 03:00:01 unassigned /USR/SBIN/CRON[3949]: (www-data) CMD ([ -x /usr/lib/cgi-bin/awstats.pl -a -f /etc/awstats/awstats.conf -a -r /var/log/apache/acces$ Jan 20 03:02:48 unassigned kernel: [371919.642705] ata3.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x0 Jan 20 03:02:48 unassigned kernel: [371919.642754] ata3.00: BMDMA stat 0x24 Jan 20 03:02:48 unassigned kernel: [371919.642779] ata3.00: cmd 25/00:08:37:59:e2/00:00:42:00:00/e0 tag 0 dma 4096 in Jan 20 03:02:48 unassigned kernel: [371919.642780] res 51/01:00:37:59:e2/01:00:42:00:00/e0 Emask 0x1 (device error) Jan 20 03:02:48 unassigned kernel: [371919.642824] ata3.00: status: { DRDY ERR } Jan 20 03:02:48 unassigned kernel: [371919.657647] ata3.00: configured for UDMA/133 Jan 20 03:02:48 unassigned kernel: [371919.657661] ata3: EH complete Jan 20 03:02:50 unassigned kernel: [371921.857580] ata3.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x0 Jan 20 03:02:50 unassigned kernel: [371921.857620] ata3.00: BMDMA stat 0x24 Jan 20 03:02:50 unassigned kernel: [371921.857645] ata3.00: cmd 25/00:08:37:59:e2/00:00:42:00:00/e0 tag 0 dma 4096 in Jan 20 03:02:50 unassigned kernel: [371921.857646] res 51/01:00:37:59:e2/01:00:42:00:00/e0 Emask 0x1 (device error) Jan 20 03:02:50 unassigned kernel: [371921.857688] ata3.00: status: { DRDY ERR } Jan 20 03:02:50 unassigned kernel: [371921.881468] ata3.00: configured for UDMA/133 Jan 20 03:02:54 unassigned kernel: [371921.881479] ata3: EH complete Jan 20 03:02:54 unassigned kernel: [371924.081382] ata3.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x0 Jan 20 03:02:54 unassigned kernel: [371924.081417] ata3.00: BMDMA stat 0x24 Jan 20 03:02:54 unassigned kernel: [371924.081443] ata3.00: cmd 25/00:08:37:59:e2/00:00:42:00:00/e0 tag 0 dma 4096 in Jan 20 03:02:54 unassigned kernel: [371924.081444] res 51/01:00:37:59:e2/01:00:42:00:00/e0 Emask 0x1 (device error) Jan 20 03:02:54 unassigned kernel: [371924.081487] ata3.00: status: { DRDY ERR } Jan 20 03:02:54 unassigned kernel: [371924.105252] ata3.00: configured for UDMA/133 Jan 20 03:02:54 unassigned kernel: [371924.105261] ata3: EH complete Jan 20 03:02:54 unassigned kernel: [371933.656925] sd 2:0:0:0: [sda] 1465149168 512-byte hardware sectors (750156 MB) Jan 20 03:02:54 unassigned kernel: [371933.656941] sd 2:0:0:0: [sda] Write Protect is off Jan 20 03:02:54 unassigned kernel: [371933.656944] sd 2:0:0:0: [sda] Mode Sense: 00 3a 00 00 Jan 20 03:02:54 unassigned kernel: [371933.656956] sd 2:0:0:0: [sda] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA Jan 20 03:02:54 unassigned kernel: [371933.656972] sd 2:0:0:0: [sda] 1465149168 512-byte hardware sectors (750156 MB) Jan 20 03:02:54 unassigned kernel: [371933.656979] sd 2:0:0:0: [sda] Write Protect is off Jan 20 03:02:54 unassigned kernel: [371933.656982] sd 2:0:0:0: [sda] Mode Sense: 00 3a 00 00 Jan 20 03:02:54 unassigned kernel: [371933.656993] sd 2:0:0:0: [sda] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA Jan 20 03:03:34 unassigned kernel: [371966.060069] ata3.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x0 Jan 20 03:05:48 unassigned kernel: [371971.776846] ata3.00: BMDMA stat 0x24 Jan 20 03:05:48 unassigned kernel: [371971.776871] ata3.00: cmd 25/00:18:87:10:ee/00:00:42:00:00/e0 tag 0 dma 12288 in Jan 20 03:05:48 unassigned kernel: [371971.776872] res 51/01:00:87:10:ee/01:00:42:00:00/e0 Emask 0x1 (device error) Jan 20 03:05:48 unassigned kernel: [371971.776914] ata3.00: status: { DRDY ERR } Jan 20 03:05:48 unassigned kernel: [371971.800668] ata3.00: configured for UDMA/133 Jan 20 03:05:48 unassigned kernel: [371971.800687] ata3: EH complete Jan 20 03:05:48 unassigned kernel: [371974.157850] ata3.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x0 Jan 20 03:05:48 unassigned kernel: [371974.157885] ata3.00: BMDMA stat 0x24 Jan 20 03:05:48 unassigned kernel: [371974.157911] ata3.00: cmd 25/00:18:87:10:ee/00:00:42:00:00/e0 tag 0 dma 12288 in Jan 20 03:05:48 unassigned kernel: [371974.157912] res 51/01:00:88:10:ee/01:00:42:00:00/e0 Emask 0x1 (device error) Jan 20 03:05:48 unassigned kernel: [371974.157956] ata3.00: status: { DRDY ERR } Jan 20 03:05:48 unassigned kernel: [371974.179773] ata3.00: configured for UDMA/133 Jan 20 03:05:48 unassigned kernel: [371974.179786] ata3: EH complete Jan 20 03:05:48 unassigned kernel: [371976.398570] ata3.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x0 Jan 20 03:05:48 unassigned kernel: [371976.398610] ata3.00: BMDMA stat 0x24 Jan 20 03:05:48 unassigned kernel: [371976.398635] ata3.00: cmd 25/00:18:87:10:ee/00:00:42:00:00/e0 tag 0 dma 12288 in Jan 20 03:05:48 unassigned kernel: [371976.398636] res 51/01:00:88:10:ee/01:00:42:00:00/e0 Emask 0x1 (device error) Jan 20 03:05:48 unassigned kernel: [371976.398678] ata3.00: status: { DRDY ERR } Jan 20 03:05:48 unassigned kernel: [371976.423477] ata3.00: configured for UDMA/133 Jan 20 03:05:48 unassigned kernel: [371976.423495] sd 2:0:0:0: [sda] Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE,SUGGEST_OK Jan 20 03:05:48 unassigned kernel: [371976.423498] sd 2:0:0:0: [sda] Sense Key : Medium Error [current] [descriptor] Jan 20 03:05:48 unassigned kernel: [371976.423501] Descriptor sense data with sense descriptors (in hex): Jan 20 03:05:48 unassigned kernel: [371976.423503] 72 03 13 00 00 00 00 0c 00 0a 80 00 00 00 00 00 Jan 20 03:05:48 unassigned kernel: [371976.423508] 42 ee 10 88 Jan 20 03:05:48 unassigned kernel: [371976.423510] sd 2:0:0:0: [sda] Add. Sense: Address mark not found for data field Jan 20 03:05:48 unassigned kernel: [371976.423515] end_request: I/O error, dev sda, sector 1122898056 Jan 20 03:05:48 unassigned kernel: [371976.423536] ata3: EH complete Jan 20 03:05:48 unassigned kernel: [371978.630504] ata3.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x0 Jan 20 03:05:48 unassigned kernel: [371978.630547] ata3.00: BMDMA stat 0x24

    Read the article

  • How to GET a read-only vs editable resource in REST style?

    - by Val
    I'm fairly familiar with REST principles, and have read the relevant dissertation, Wikipedia entry, a bunch of blog posts and StackOverflow questions on the subject, but still haven't found a straightforward answer to a common case: I need to request a resource to display. Depending on the resource's state, I need to render either a read-only or an editable representation. In both cases, I need to GET the resource. How do I construct a URL to get the read-only or editable version? If my user follows a link to GET /resource/<id>, that should suffice to indicate to me that s/he needs the read-only representation. But if I need to server up an editable form, what does that URL look like? GET /resource/<id>/edit is obvious, but it contains a verb in the URL. Changing that to GET /resource/<id>/editable solves that problem, but at a seemingly superficial level. Is that all there is to it -- change verbs to adjectives? If instead I use POST to retrieve the editable version, then how do I distinguish between the POST that initially retrieves it, vs the POST that saves it? My (weak) excuse for using POST would be that retrieving an editable version would cause a change of state on the server: locking the resource. But that only holds if my requirements are to implement such a lock, which is not always the case. PUT fails for the same reason, plus PUT is not enabled by default on the Web servers I'm running, so there are practical reasons not to use it (and DELETE). Note that even in the editable state, I haven't made any changes yet; presumably when I submit the resource to the Web server again, I'd POST it. But to get something that I can later POST, the server has to first serve up a particular representation. I guess another approach would be to have separate resources at the collection level: GET /read-only/resource/<id> and GET /editable/resource/<id> or GET /resource/read-only/<id> and GET /resource/editable/<id> ... but that looks pretty ugly to me. Thoughts?

    Read the article

  • Read and write from a byte stream if the endianess of the data is different from that of the current

    - by Sam Holder
    I have a stream of bytes which contains a flag which identifies the endianness of the data in the header. I want to read the doubles from the stream, which will presumably need to be different if the endianness of the data in the header is different? I am currently using a BinaryReader and calling ReadDouble to read the data from the stream, but if the endianness flag indicates that the data stream has a different endianness than the machine architecture then presumably this will not work? How should this be handled? Should I check the endianness of my data against that of the current machine then when I want to read a double instead read the bytes raw into a byte array and do array.Reverse to reverse the data before using BitConverter.ToDouble () with the reversed data and a zero offset? I could just test this but I do not have a source of data for both endianness so am a bit concerned about creating test data to test the parsing and this being different from what 'real' data might look like.

    Read the article

  • Can you force a crash if a write occurs to a given memory location with finer than page granularity?

    - by Joseph Garvin
    I'm writing a program that for performance reasons uses shared memory (alternatives have been evaluated, and they are not fast enough for my task, so suggestions to not use it will be downvoted). In the shared memory region I am writing many structs of a fixed size. There is one program responsible for writing the structs into shared memory, and many clients that read from it. However, there is one member of each struct that clients need to write to (a reference count, which they will update atomically). All of the other members should be read only to the clients. Because clients need to change that one member, they can't map the shared memory region as read only. But they shouldn't be tinkering with the other members either, and since these programs are written in C++, memory corruption is possible. Ideally, it should be as difficult as possible for one client to crash another. I'm only worried about buggy clients, not malicious ones, so imperfect solutions are allowed. I can try to stop clients from overwriting by declaring the members in the header they use as const, but that won't prevent memory corruption (buffer overflows, bad casts, etc.) from overwriting. I can insert canaries, but then I have to constantly pay the cost of checking them. Instead of storing the reference count member directly, I could store a pointer to the actual data in a separate mapped write only page, while keeping the structs in read only mapped pages. This will work, the OS will force my application to crash if I try to write to the pointed to data, but indirect storage can be undesirable when trying to write lock free algorithms, because needing to follow another level of indirection can change whether something can be done atomically. Is there any way to mark smaller areas of memory such that writing them will cause your app to blow up? Some platforms have hardware watchpoints, and maybe I could activate one of those with inline assembly, but I'd be limited to only 4 at a time on 32-bit x86 and each one could only cover part of the struct because they're limited to 4 bytes. It'd also make my program painful to debug ;)

    Read the article

  • How can I read a DBF file with incorrectly defined column data types using ADO.NET?

    - by Jason
    I have a several DBF files generated by a third party that I need to be able to query. I am having trouble because all of the column types have been defined as characters, but the data within some of these fields actually contain binary data. If I try to read these fields using an OleDbDataReader as anything other than a string or character array, I get an InvalidCastException thrown, but I need to be able to read them as a binary value or at least cast/convert them after they are read. The columns that actually DO contain text are being returned as expected. For example, the very first column is defined as a character field with a length of 2 bytes, but the field contains a 16-bit integer. I have written the following test code to read the first column and convert it to the appropriate data type, but the value is not coming out right. The first row of the database has a value of 17365 (0x43D5) in the first column. Running the following code, what I end up getting is 17215 (0x433F). I'm pretty sure it has to do with using the ASCII encoding to get the bytes from the string returned by the data reader, but I'm not sure of another way to get the value into the format that I need, other that to write my own DBF reader and bypass ADO.NET altogether which I don't want to do unless I absolutely have to. Any help would be greatly appreciated. byte[] c0; int i0; string con = @"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=C:\ASTM;Extended Properties=dBASE III;User ID=Admin;Password=;"; using (OleDbConnection c = new OleDbConnection(con)) { c.Open(); OleDbCommand cmd = c.CreateCommand(); cmd.CommandText = "SELECT * FROM astm2007"; OleDbDataReader dr = cmd.ExecuteReader(); while (dr.Read()) { c0 = Encoding.ASCII.GetBytes(dr.GetValue(0).ToString()); i0 = BitConverter.ToInt16(c0, 0); } dr.Dispose(); }

    Read the article

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

< Previous Page | 111 112 113 114 115 116 117 118 119 120 121 122  | Next Page >