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  • Read Erotica on the iPad

    Requirements: -- An iPad -- Free Stanza reader for iPad. -- Free Stanza Desktop software (Runs on Window PC and Mac). -- Internet connection and a small amount of intelligence. Steps: For a detail... [Author: Chris Smith - Computers and Internet - May 04, 2010]

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  • Read about Interface-Based Programming in C#

    - by Editor
    Learn to program using interfaces by reading C# Online.NET articles like Interfaces and Abstract Classes. And, here is an excerpt from a VSLive! article on Interface-Based Programming in C#. "Interfaces help define a contract, or agreement, between your application and other objects. This agreement indicates what sort of methods, properties and events are exposed by an object. [...]

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  • List and Read Text Files

    This sample takes files from a folder (in this situation, text files), and lists them in a listbox. Then, the user can click on a particular file, and display the text from the selected text file, in the textbox to the right of the listbox.

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  • file read performance degrades as number of files increases

    - by bfallik-bamboom
    We're observing poor file read IO results that we'd like to better understand. We can use fio to write 100 files with a sustained aggregate throughput of ~700MB/s. When we switch the test to read instead of write, the aggregate throughput is only ~55MB/s. The drop seems related to the number of files since the throughput for read and write are comparable for a single file then diverge proportionally as we increase the number of files. The test server has 24 CPU cores, 48GB of memory, and is running CentOS 6.0. The disk hardware is a RAID 6 array with 12 disks and a Dell H800 controller. This device is partitioned with ext4 using the default settings. Increasing the readahead (using blockdev) improves the read throughput significantly but it still doesn't match write speed. For instance, increasing the readahead from 128KB to 1M improved the read throughput to ~145MB/s. Is this a known performance issue in our OS/disk/filesystem configuration? If so, how can we tell? If not, what tools or tests can we use to further isolate the issue? Thanks.

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  • Outlook 2010 stopped marking messages as read after reading them

    - by dunxd
    Yesterday I noticed that Outlook 2010 had stopped marking messages as read unless I right click and select Mark as Read. I have checked the Reading Panel settings (it's set to 0 seconds), but I don't use the reading panel to read my mail. When I open a message by doubleclicking it, then close it again, the message is still marked as Read. Outlook 2010 is connecting to Exchange Server 2003. This was working fine until yesterday. As far as I know there have been no config changes at either the client or server end.

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  • Is C# becoming harder to read? [closed]

    - by Avi
    As C# has progressed, many language features have been added. It has come to the point where it's becoming unreadable for me. As an example, consider the following code snip from Caliburn.Micro code here: container = CompositionHost.Initialize( new AggregateCatalog( AssemblySource.Instance. Select(x => new AssemblyCatalog(x)) .OfType<ComposablePartCatalog>() ) ); Now, this is just a small example. I have a number of questions: Is this a common or known problem? Is the C# community finding the same? Is this an issue with the language, or is it the style used by the developer? Are there any simple solutions to better understand others code and avoid writing code in this way?

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  • Should I read Kochan's "Programming in C" (10 years old) [on hold]

    - by notypist
    I plan on learning Obj-C and so I decided to do it by the book and learn C first. The problem: S.G. Kochan's highly acclaimed book "Programming in C" (3rd edition) is almost ten years old now1. I really want to get started and everywhere I looked this seemed like the book for beginners with an assumed zero-knowledge in programming2. So, should I buy it or not? 1: A 4th edition is available to preorder but it's only due in March, 2014! 2: I know some HTML, CSS, and a tiny bit of PHP.

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  • Why use buffers to read/write Streams

    - by James Hay
    Following reading various questions on reading and writing Streams, all the various answers define something like this as the correct way to do it: private void CopyStream(Stream input, Stream output) { byte[] buffer = new byte[16 * 1024]; int read; while ((read = input.Read(buffer, 0, buffer.Length)) > 0) { output.Write(buffer, 0, read); } } Two questions: Why read and write in these smaller chunks? What is the significance of the buffer size used?

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  • PowerShell PSCX Read-Archive: Cannot bind parameter... problem

    - by Robert
    I'm running across a problem I can't seem to wrap my head around using the Read-Archive cmdlet available via PowerShell Community Extensions (v2.0.3782.38614). Here is a cut down sample used to exhibit the problem I'm running into: $mainPath = "p:\temp" $dest = Join-Path $mainPath "ps\CenCodes.zip" Read-Archive -Path $dest -Format zip Running the above produces the following error: Read-Archive : Cannot bind parameter 'Path'. Cannot convert the "p:\temp\ps\CenCodes.zip" value of type "System.String" to type "Pscx.IO.PscxPathInfo". At line:3 char:19 + Read-Archive -Path <<<< $dest -Format zip + CategoryInfo : InvalidArgument: (:) [Read-Archive], ParameterBindingException + FullyQualifiedErrorId : CannotConvertArgumentNoMessage,Pscx.Commands.IO.Compression.ReadArchiveCommand If I do not use Join-Path to build the path passed to Read-Archive it works, as in this example: $mainPath = "p:\temp" $path = $mainPath + "\ps\CenCodes.zip" Read-Archive -Path $path -Format zip Output from above: ZIP Folder: CenCodes.zip#\ Index LastWriteTime Size Ratio Name ----- ------------- ---- ----- ---- 0 6/17/2010 2:03 AM 3009106 24.53 % CenCodes.xls Even more confusing is if I compare the two variables passed as the Path argument in the two Read-Archive samples above, they seem identical: This... Write-Host "dest=$dest" Write-Host "path=$path" Write-Host ("path -eq dest is " + ($dest -eq $path).ToString()) Outputs... dest=p:\temp\ps\CenCodes.zip path=p:\temp\ps\CenCodes.zip path -eq dest is True Anyone have any ideas as to why the first sample gripes but the second one works fine?

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  • Input/output (read) errors in Bacula while setting up a Tape Drive + Autochanger

    - by Kyle Brandt
    When running the label barcode command in bacula I am getting Input/output errors. I am just getting started in trying to set this up: Connecting to Storage daemon TapeDevice at ny-back01.ny.stackoverflow.com:9103 ... Sending label command for Volume "ACJ332" Slot 1 ... 3307 Issuing autochanger "unload slot 8, drive 0" command. 3304 Issuing autochanger "load slot 1, drive 0" command. 3305 Autochanger "load slot 1, drive 0", status is OK. block.c:1010 Read error on fd=5 at file:blk 0:0 on device "ULTRIUM-HH4" (/dev/st0). ERR=Input/output error. 3000 OK label. VolBytes=64512 DVD=0 Volume="ACJ332" Device="ULTRIUM-HH4" (/dev/st0) Catalog record for Volume "ACJ332", Slot 1 successfully created. Sending label command for Volume "ACJ331" Slot 2 ... 3307 Issuing autochanger "unload slot 1, drive 0" command. 3304 Issuing autochanger "load slot 2, drive 0" command. 3305 Autochanger "load slot 2, drive 0", status is OK. block.c:1010 Read error on fd=5 at file:blk 0:0 on device "ULTRIUM-HH4" (/dev/st0). ERR=Input/output error. 3000 OK label. VolBytes=64512 DVD=0 Volume="ACJ331" Device="ULTRIUM-HH4" (/dev/st0) Catalog record for Volume "ACJ331", Slot 2 successfully created. Sending label command for Volume "ACJ328" Slot 3 ... 3307 Issuing autochanger "unload slot 2, drive 0" command. 3304 Issuing autochanger "load slot 3, drive 0" command. 3305 Autochanger "load slot 3, drive 0", status is OK. block.c:1010 Read error on fd=5 at file:blk 0:0 on device "ULTRIUM-HH4" (/dev/st0). ERR=Input/output error. 3000 OK label. VolBytes=64512 DVD=0 Volume="ACJ328" Device="ULTRIUM-HH4" (/dev/st0) Catalog record for Volume "ACJ328", Slot 3 successfully created. Sending label command for Volume "ACJ329" Slot 4 ... 3307 Issuing autochanger "unload slot 3, drive 0" command. 3304 Issuing autochanger "load slot 4, drive 0" command. 3305 Autochanger "load slot 4, drive 0", status is OK. block.c:1010 Read error on fd=5 at file:blk 0:0 on device "ULTRIUM-HH4" (/dev/st0). ERR=Input/output error. 3000 OK label. VolBytes=64512 DVD=0 Volume="ACJ329" Device="ULTRIUM-HH4" (/dev/st0) Catalog record for Volume "ACJ329", Slot 4 successfully created. Sending label command for Volume "ACJ335" Slot 5 ... 3307 Issuing autochanger "unload slot 4, drive 0" command. 3304 Issuing autochanger "load slot 5, drive 0" command. 3305 Autochanger "load slot 5, drive 0", status is OK. block.c:1010 Read error on fd=5 at file:blk 0:0 on device "ULTRIUM-HH4" (/dev/st0). ERR=Input/output error. 3000 OK label. VolBytes=64512 DVD=0 Volume="ACJ335" Device="ULTRIUM-HH4" (/dev/st0) Catalog record for Volume "ACJ335", Slot 5 successfully created. Sending label command for Volume "ACJ334" Slot 6 ... 3307 Issuing autochanger "unload slot 5, drive 0" command. 3304 Issuing autochanger "load slot 6, drive 0" command. 3305 Autochanger "load slot 6, drive 0", status is OK. block.c:1010 Read error on fd=5 at file:blk 0:0 on device "ULTRIUM-HH4" (/dev/st0). ERR=Input/output error. 3000 OK label. VolBytes=64512 DVD=0 Volume="ACJ334" Device="ULTRIUM-HH4" (/dev/st0) Catalog record for Volume "ACJ334", Slot 6 successfully created. Sending label command for Volume "ACJ333" Slot 7 ... 3307 Issuing autochanger "unload slot 6, drive 0" command. 3304 Issuing autochanger "load slot 7, drive 0" command. 3305 Autochanger "load slot 7, drive 0", status is OK. block.c:1010 Read error on fd=5 at file:blk 0:0 on device "ULTRIUM-HH4" (/dev/st0). ERR=Input/output error. 3000 OK label. VolBytes=64512 DVD=0 Volume="ACJ333" Device="ULTRIUM-HH4" (/dev/st0) Catalog record for Volume "ACJ333", Slot 7 successfully created. Sending label command for Volume "ACJ330" Slot 8 ... 3307 Issuing autochanger "unload slot 7, drive 0" command. Bacula-dir: # Definition of file storage device Storage { Name = TapeDevice # Do not use "localhost" here Address = ny-back01.... # N.B. Use a fully qualified name here SDPort = 9103 Password = "..." Device = ULTRIUM-HH4 Media Type = LTO-4 Media Type = File Autochanger = Yes } Bacula-sd: Autochanger { Name = StorageLoader1U Device = ULTRIUM-HH4 Changer Command = "/etc/bacula/scripts/mtx-changer %c %o %S %a %d" Changer Device = /dev/sg5 } Device { Name = ULTRIUM-HH4 Media Type = LTO-4 Archive Device = /dev/st0 AutomaticMount = yes; AlwaysOpen = yes; RemovableMedia = yes; RandomAccess = no; AutoChanger = yes; RandomAccess = no; } Anyone knows what this means / why I am getting this?

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  • Interrupt an Http Request blocked in read() on Android

    - by twk
    Using the Apache Http stack on Android, I'm trying to force a thread out of a call to read. This is what the stack looks like: OSNetworkSystem.receiveStreamImpl(FileDescriptor, byte[], int, int, int) line: not available [native method] OSNetworkSystem.receiveStream(FileDescriptor, byte[], int, int, int) line: 478 PlainSocketImpl.read(byte[], int, int) line: 565 SocketInputStream.read(byte[], int, int) line: 87 SocketInputBuffer(AbstractSessionInputBuffer).fillBuffer() line: 103 SocketInputBuffer(AbstractSessionInputBuffer).read(byte[], int, int) line: 134 IdentityInputStream.read(byte[], int, int) line: 86 EofSensorInputStream.read(byte[], int, int) line: 159 Fetcher.readStream() line: 89 I've tried InputStream.close(), Thread.Interrupt(), and HttpUriRequest.abort(), without any success. Any ideas? I'm also open to some kind of non-blocking IO, but I don't see any way to do that with the HttpUriRequest object. Thanks!

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  • Django dislaying upload file content

    - by dana
    hello, i have an application that loads different documents to the server, and allows users to read documents' content. i am uploading the documents to the server, and then i try to read the courses by id, like: def view_course(request,id): u = Courses.objects.get(pk=id) etc But i don't find anywhere : how can i actually read the content of a /.doc/.pdf/.txt and display it on a web page? thanks in advance!

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  • Java client server sending bytes receiver listens indefinitely

    - by Rob
    Hello, I'm trying to write a Java program for Windows that involves communication with a server program located on a foreign machine.My program successfully connects to the server, successfully writes a byte array to it, and waits for a response. I know that the server is printing bytes (the response) back to me one byte at a time. I've tried using a DataInputStream object with various methods (read, readByte etc.), I've tried using a BufferedReader object with its methods (read, readLine etc.) but all the reader objects and various methods that I've used all come up against the same problem. The bytes are being successfully read (each time a byte or bytes are read, I can print them to the console, and they are what I'd expect them to be). The problem is that my reader doesn't know when to stop reading. Even if the server has sent all its bytes, the reader function on my end waits for more data, indefinitely, and so the program hangs at the read function. This problem seems to affect all the techniques that I have tried. I've been running tests with a simple client program and server program, each about 40 or 50 lines long, where the client connects to the server, and sends some bytes to it. All the techniques I've tried for the server reader result in the same problem mentioned above (the server hangs waiting for more input from the client, even though it has sent all its data). I'm really desperate for some help on this. It's important that I get this program finished soon, and it's basically complete except for this communication issue. Any help is much appreciated! -Rob

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  • Fast read of certain bytes of multiple files in C/C++

    - by Alejandro Cámara
    I've been searching in the web about this question and although there are many similar questions about read/write in C/C++, I haven't found about this specific task. I want to be able to read from multiple files (256x256 files) only sizeof(double) bytes located in a certain position of each file. Right now my solution is, for each file: Open the file (read, binary mode): fstream fTest("current_file", ios_base::out | ios_base::binary); Seek the position I want to read: fTest.seekg(position*sizeof(test_value), ios_base::beg); Read the bytes: fTest.read((char *) &(output[i][j]), sizeof(test_value)); And close the file: fTest.close(); This takes about 350 ms to run inside a for{ for {} } structure with 256x256 iterations (one for each file). Q: Do you think there is a better way to implement this operation? How would you do it?

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  • Reading in a file - Warning Message in R

    - by Sheila
    I have a file that has 22268 rows BY 2521 columns. When I try to read in the file using this line of code: file <- read.table(textfile, skip=2, header=TRUE, sep="\t", fill=TRUE, blank.lines.skip=FALSE) I get the following error: Warning message: In scan(file, what, nmax, sep, dec, quote, skip, nlines, na.strings, : number of items read is not a multiple of the number of columns I also used this command to see what rows had an incorrect number of columns: x <-count.fields("train.gct", sep="\t", skip=2) which(x != 2521) and got back a list of about 20 rows that were incorrect. Is there a way to fill these rows with NA values? I thought that is what the "fill" parameter does in the read.table function, but it doesn't appear so. Any help would be greatly appreciated. Thank you.

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  • Bash script 'while read' loop causes 'broken pipe' error when run with GNU Parallel

    - by Joe White
    According to the GNU Parallel mailing list this is not a GNU Parallel-specific problem. They suggested that I post my problem here. The error I'm getting is a "broken pipe" error, but I feel I should first explain the context of my problem and what causes this error. It happens when trying to use any bash script containing a 'while read' loop in GNU Parallel. I have a basic bash script like this: #!/bin/bash # linkcheck.sh while read domain do host "$domain" done Assume that I want to pipe in a large list (250mb say). cat urllist | ./linkcheck.sh Running host command on 250mb worth of URLs is rather slow. To speed things up I want to break up the input into chunks before piping it and then run multiple jobs in parallel. GNU Parallel is capable of doing this. cat urllist | parallel --pipe -j0 parallel ./linkcheck.sh {} {} is substituted by the contents of urllist line-by-line. Assume that my systems default setup is capable of running 500ish jobs per instance of parallel. To get round this limitation we can parallelize Parallel itself: cat urllist | parallel -j10 --pipe parallel -j0 ./linkcheck.sh {} This will run 5000'ish jobs. It will also, sadly, cause the error "broken pipe" (bash FAQ). Yet the script starts to work if I remove the while read loop and take input directly from whatever is fed into {} e.g., #!/bin/bash # linkchecker.sh domain="$1" host "$1" Why will it not work with a while read loop? Is it safe to just turn off the SIGPIPE signal to stop the "broken pipe" message, or will that have side effects such as data corruption? Thanks for reading.

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  • Read access to Active Directory property (uSNCreated)

    - by Tom Ligda
    I have an issue with read access to the uSNCreated property when doing LDAP searches. If I do an LDAP search with a user that is a member of the Domain Admins group (UserA), I can see the uSNCreated property for every user. The problem is that if I do an LDAP search with a user (UserB) that is not a member of the Domain Admins group, I can see the uSNCreated property for some users (UserGroupA) and not for some users (UserGroupB). When I look at the users in UserGroupA and compare them to the users in UserGroupB, I see a crucial difference in the "Security" tab. The users in UserGroupA have the "Include inheritable permissions from this object's parent" unchecked. The users in UserGroupB have that option checked. I also noticed that the users in UserGroupA are users that were created earlier. The users in UserGroupB are users created recently. It's difficult to quantify, but I estimate the border between creation time between the users in UserGroupA and UserGroupB is about 6 months ago. What can cause the user creation to default to having that security property checked as opposed to unchecked? A while back (maybe around 6 months ago?) I changed the domain functional level from Windows Server 2003 to Windows Server 2008 R2. Would that have had this effect? (I can't exactly downgrade the domain functional level to test it out.) Is this security property actually the cause of the issue with read access to the uSNChanged property on LDAP searches? It seems correlated, but I'm not sure about causation. What I want in the end is for all authenticated users to have read access to the uSNCreated property for all users when doing an LDAP search. I would also be OK if I could grant read access for that property to an AD group. Then I can control access by adding members to the group.

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  • Problems with "Read Only" on a Samba share from Windows machines

    - by fistameeny
    Hi, We have a Ubuntu 10.04 Server that has a bunch of Samba shares on it that Windows workstations connect to. Each Windows workstation has a valid username/password to access the shares, which have restricted access governed by Samba. The problem we are experiencing is that Samba doesn't seem to be able to mimic the Windows way of handling "Read Only" attributes. Say I have two users, UserA and UserB, both a group called Staff - UserA creates a file that is readable/writeable by the group (ie. chmod rwxrwx---). If UserA then sets the "Read Only" flag, this changes the permissions to r-xr-x--- (i.e. no write for anyone). As UserB is in the same group as UserA, they should be able to remove the "Read Only" permission - however, they can't as Samba won't allow it. Is there a way to force Samba to allow users within the same group to remove the "Read Only" from a file not created by them? Edit: The Samba smb.conf is as follows: The share is defined in the smb.conf as: [global] log file = /var/log/samba/log.%m passwd chat = *Enter\snew\s*\spassword:* %n\n *Retype\snew\s*\spassword:* %n\n *password\supdated\ssuccessfully* . obey pam restrictions = yes map to guest = bad user encrypt passwords = true passwd program = /usr/bin/passwd %u passdb backend = tdbsam dns proxy = no netbios name = ubsrv server string = ubsrv unix password sync = yes os level = 20 syslog = 0 usershare allow guests = yes panic action = /usr/share/samba/panic-action %d max log size = 1000 pam password change = yes workgroup = workgroup [Projects] valid users = @Staff writeable = yes user = @Staff create mode = 0777 path = /srv/samba/Projects directory mode = 0777 store dos attributes = Yes The folder itself looks like this: ls -l /srv/samba/ drwxrwxrwx 2 nobody Staff 4096 2010-11-04 10:09 Projects Thanks in advance, Matt

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  • Problems with "Read Only" on a Samba share from Windows machines

    - by fistameeny
    We have a Ubuntu 10.04 Server that has a bunch of Samba shares on it that Windows workstations connect to. Each Windows workstation has a valid username/password to access the shares, which have restricted access governed by Samba. The problem we are experiencing is that Samba doesn't seem to be able to mimic the Windows way of handling "Read Only" attributes. Say I have two users, UserA and UserB, both a group called Staff - UserA creates a file that is readable/writeable by the group (ie. chmod rwxrwx---). If UserA then sets the "Read Only" flag, this changes the permissions to r-xr-x--- (i.e. no write for anyone). As UserB is in the same group as UserA, they should be able to remove the "Read Only" permission - however, they can't as Samba won't allow it. Is there a way to force Samba to allow users within the same group to remove the "Read Only" from a file not created by them? Edit: The Samba smb.conf is as follows: The share is defined in the smb.conf as: [global] log file = /var/log/samba/log.%m passwd chat = *Enter\snew\s*\spassword:* %n\n *Retype\snew\s*\spassword:* %n\n *password\supdated\ssuccessfully* . obey pam restrictions = yes map to guest = bad user encrypt passwords = true passwd program = /usr/bin/passwd %u passdb backend = tdbsam dns proxy = no netbios name = ubsrv server string = ubsrv unix password sync = yes os level = 20 syslog = 0 usershare allow guests = yes panic action = /usr/share/samba/panic-action %d max log size = 1000 pam password change = yes workgroup = workgroup [Projects] valid users = @Staff writeable = yes user = @Staff create mode = 0777 path = /srv/samba/Projects directory mode = 0777 store dos attributes = Yes The folder itself looks like this: ls -l /srv/samba/ drwxrwxrwx 2 nobody Staff 4096 2010-11-04 10:09 Projects Thanks in advance, Matt

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  • Word Document Turns to Read-Only

    - by Psycho Bob
    I am running into an issue with a user whose Word document is somehow turning itself into Read-Only. The user is using Word 2003 and is accessing a document that is in a Server 2008 share. The document itself starts out as a normal, editable document (user has Full Control permissions), and the user is able to save and do the 'normal' things you would do to a document. However, after a couple of saves, the document turns to Read-Only (according to the title bar) even though the Read-Only attribute is not checked on the document's properties. Here is some additional information about the situation: *User has approximately 5-8 Word documents open at a time *User saves the document frequently (sometimes at a frequency of once per minute) *Once the document is closed it will open as a normal document if reopened *When the document does turn to Read-Only the user will do a "Save As" on the document and save it as FILENAME # where # is some increment of how many times this has happened (some documents are up to their 30th iteration) I understand that there is probably some room for user education here and that they could just be copying the RO document to a new one, closing and opening the RO doc, then copying all the information back. However, I would like to get to the route cause of the problem and try to stop it from happening in the first place. UPDATE: Apparently the reinstall did not fix the issue. I researched the issue a bit more and found that disabling the background save may take care of it, but I haven't had a chance to try it yet. Does anyone else have any other ideas?

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  • Read access to Active Directory property (uSNChanged)

    - by Tom Ligda
    I have an issue with read access to the uSNChanged property when doing LDAP searches. If I do an LDAP search with a user that is a member of the Domain Admins group (UserA), I can see the uSNChanged property for every user. The problem is that if I do an LDAP search with a user (UserB) that is not a member of the Domain Admins group, I can see the uSNChanged property for some users (UserGroupA) and not for some users (UserGroupB). When I look at the users in UserGroupA and compare them to the users in UserGroupB, I see a crucial difference in the "Security" tab. The users in UserGroupA have the "Include inheritable permissions from this object's parent" unchecked. The users in UserGroupB have that option checked. I also noticed that the users in UserGroupA are users that were created earlier. The users in UserGroupB are users created recently. It's difficult to quantify, but I estimate the border between creation time between the users in UserGroupA and UserGroupB is about 6 months ago. What can cause the user creation to default to having that security property checked as opposed to unchecked? A while back (maybe around 6 months ago?) I changed the domain functional level from Windows Server 2003 to Windows Server 2008 R2. Would that have had this effect? (I can't exactly downgrade the domain functional level to test it out.) Is this security property actually the cause of the issue with read access to the uSNChanged property on LDAP searches? It seems correlated, but I'm not sure about causation. What I want in the end is for all authenticated users to have read access to the uSNChanged property for all users when doing an LDAP search. I would also be OK if I could grant read access for that property to an AD group. Then I can control access by adding members to the group.

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  • Implementing an async "read all currently available data from stream" operation

    - by Jon
    I recently provided an answer to this question: C# - Realtime console output redirection. As often happens, explaining stuff (here "stuff" was how I tackled a similar problem) leads you to greater understanding and/or, as is the case here, "oops" moments. I realized that my solution, as implemented, has a bug. The bug has little practical importance, but it has an extremely large importance to me as a developer: I can't rest easy knowing that my code has the potential to blow up. Squashing the bug is the purpose of this question. I apologize for the long intro, so let's get dirty. I wanted to build a class that allows me to receive input from a console's standard output Stream. Console output streams are of type FileStream; the implementation can cast to that, if needed. There is also an associated StreamReader already present to leverage. There is only one thing I need to implement in this class to achieve my desired functionality: an async "read all the data available this moment" operation. Reading to the end of the stream is not viable because the stream will not end unless the process closes the console output handle, and it will not do that because it is interactive and expecting input before continuing. I will be using that hypothetical async operation to implement event-based notification, which will be more convenient for my callers. The public interface of the class is this: public class ConsoleAutomator { public event EventHandler<ConsoleOutputReadEventArgs> StandardOutputRead; public void StartSendingEvents(); public void StopSendingEvents(); } StartSendingEvents and StopSendingEvents do what they advertise; for the purposes of this discussion, we can assume that events are always being sent without loss of generality. The class uses these two fields internally: protected readonly StringBuilder inputAccumulator = new StringBuilder(); protected readonly byte[] buffer = new byte[256]; The functionality of the class is implemented in the methods below. To get the ball rolling: public void StartSendingEvents(); { this.stopAutomation = false; this.BeginReadAsync(); } To read data out of the Stream without blocking, and also without requiring a carriage return char, BeginRead is called: protected void BeginReadAsync() { if (!this.stopAutomation) { this.StandardOutput.BaseStream.BeginRead( this.buffer, 0, this.buffer.Length, this.ReadHappened, null); } } The challenging part: BeginRead requires using a buffer. This means that when reading from the stream, it is possible that the bytes available to read ("incoming chunk") are larger than the buffer. Remember that the goal here is to read all of the chunk and call event subscribers exactly once for each chunk. To this end, if the buffer is full after EndRead, we don't send its contents to subscribers immediately but instead append them to a StringBuilder. The contents of the StringBuilder are only sent back whenever there is no more to read from the stream. private void ReadHappened(IAsyncResult asyncResult) { var bytesRead = this.StandardOutput.BaseStream.EndRead(asyncResult); if (bytesRead == 0) { this.OnAutomationStopped(); return; } var input = this.StandardOutput.CurrentEncoding.GetString( this.buffer, 0, bytesRead); this.inputAccumulator.Append(input); if (bytesRead < this.buffer.Length) { this.OnInputRead(); // only send back if we 're sure we got it all } this.BeginReadAsync(); // continue "looping" with BeginRead } After any read which is not enough to fill the buffer (in which case we know that there was no more data to be read during the last read operation), all accumulated data is sent to the subscribers: private void OnInputRead() { var handler = this.StandardOutputRead; if (handler == null) { return; } handler(this, new ConsoleOutputReadEventArgs(this.inputAccumulator.ToString())); this.inputAccumulator.Clear(); } (I know that as long as there are no subscribers the data gets accumulated forever. This is a deliberate decision). The good This scheme works almost perfectly: Async functionality without spawning any threads Very convenient to the calling code (just subscribe to an event) Never more than one event for each time data is available to be read Is almost agnostic to the buffer size The bad That last almost is a very big one. Consider what happens when there is an incoming chunk with length exactly equal to the size of the buffer. The chunk will be read and buffered, but the event will not be triggered. This will be followed up by a BeginRead that expects to find more data belonging to the current chunk in order to send it back all in one piece, but... there will be no more data in the stream. In fact, as long as data is put into the stream in chunks with length exactly equal to the buffer size, the data will be buffered and the event will never be triggered. This scenario may be highly unlikely to occur in practice, especially since we can pick any number for the buffer size, but the problem is there. Solution? Unfortunately, after checking the available methods on FileStream and StreamReader, I can't find anything which lets me peek into the stream while also allowing async methods to be used on it. One "solution" would be to have a thread wait on a ManualResetEvent after the "buffer filled" condition is detected. If the event is not signaled (by the async callback) in a small amount of time, then more data from the stream will not be forthcoming and the data accumulated so far should be sent to subscribers. However, this introduces the need for another thread, requires thread synchronization, and is plain inelegant. Specifying a timeout for BeginRead would also suffice (call back into my code every now and then so I can check if there's data to be sent back; most of the time there will not be anything to do, so I expect the performance hit to be negligible). But it looks like timeouts are not supported in FileStream. Since I imagine that async calls with timeouts are an option in bare Win32, another approach might be to PInvoke the hell out of the problem. But this is also undesirable as it will introduce complexity and simply be a pain to code. Is there an elegant way to get around the problem? Thanks for being patient enough to read all of this. Update: I definitely did not communicate the scenario well in my initial writeup. I have since revised the writeup quite a bit, but to be extra sure: The question is about how to implement an async "read all the data available this moment" operation. My apologies to the people who took the time to read and answer without me making my intent clear enough.

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