When an application on a computer uses the socket system that is provided by SUA to send data, a value of -1 and an EAGAIN error are returned

Consider the following scenario:

• You run an application on a computer that has Subsystem for UNIX-based Applications (SUA) installed.
• The application uses the socket system that is provided by SUA to send data to a destination computer.
• The size of the data that is received is larger than the send-buffer (SNDBUF).

In this scenario, a value of -1 and an EAGAIN error are returned even though the data has already been sent.

Note When an application uses Winsock to send data, an EWOULDBLOCK error is returned if the size of the data that is received is larger than the send-buffer. Winsock is blocked unless all the data can be sent. However, in a non-blocking socket subsystem like SUA, the size of the data that is received can be larger than the send-buffer.

After you apply this hotfix, the system no longer returns an error in the scenario that is described in the "Symptoms" section. Instead, the system returns the number of bytes that have been sent in non-blocking sockets.

Hotfix information for SUA in Windows Server 2003 R2

A supported hotfix is available from Microsoft. However, this hotfix is intended to correct only the problem that is described in this article. Apply this hotfix only to systems that are experiencing this specific problem. This hotfix might receive additional testing. Therefore, if you are not severely affected by this problem, we recommend that you wait for the next software update that contains this hotfix.

If the hotfix is available for download, there is a "Hotfix download available" section at the top of this Knowledge Base article. If this section does not appear, contact Microsoft Customer Service and Support to obtain the hotfix.

Note If additional issues occur or if any troubleshooting is required, you might have to create a separate service request. The usual support costs will apply to additional support questions and issues that do not qualify for this specific hotfix. For a complete list of Microsoft Customer Service and Support telephone numbers or to create a separate service request, visit the following Microsoft Web site: Note The "Hotfix download available" form displays the languages for which the hotfix is available. If you do not see your language, it is because a hotfix is not available for that language.

Prerequisites

To apply this hotfix, you must have Windows Server 2003 Service Pack 2 installed. For more information, click the following article number to view the article in the Microsoft Knowledge Base:

Restart requirement

You must restart the computer after you apply this hotfix.

Hotfix replacement information

This hotfix does not replace any other hotfixes.

File information

The English version of this hotfix has the file attributes (or later file attributes) that are listed in the following table. The dates and times for these files are listed in Coordinated Universal Time (UTC). When you view the file information, it is converted to local time. To find the difference between UTC and local time, use the Time Zone tab in the Date and Time item in Control Panel.

Windows Server 2003 R2 with Service Pack 2, x86-based versions

Windows Server 2003 R2 with Service Pack 2, x64-based versions

Hotfix information for SUA in Windows Vista and Windows Server 2008

A supported hotfix is available from Microsoft. However, this hotfix is intended to correct only the problem that is described in this article. Apply this hotfix only to systems that are experiencing the problem described in this article. This hotfix might receive additional testing. Therefore, if you are not severely affected by this problem, we recommend that you wait for the next software update that contains this hotfix.

If the hotfix is available for download, there is a "Hotfix download available" section at the top of this Knowledge Base article. If this section does not appear, contact Microsoft Customer Service and Support to obtain the hotfix.

Note If additional issues occur or if any troubleshooting is required, you might have to create a separate service request. The usual support costs will apply to additional support questions and issues that do not qualify for this specific hotfix. For a complete list of Microsoft Customer Service and Support telephone numbers or to create a separate service request, visit the following Microsoft Web site: Note The "Hotfix download available" form displays the languages for which the hotfix is available. If you do not see your language, it is because a hotfix is not available for that language.

Prerequisites

To apply this hotfix, you must have Windows Server 2003 Service Pack 2 installed. For more information, click the following article number to view the article in the Microsoft Knowledge Base:

Restart requirement

You must restart the computer after you apply this hotfix.

Hotfix replacement information

This hotfix does not replace any other hotfixes.

File information

The English version of this hotfix has the file attributes (or later file attributes) that are listed in the following table. The dates and times for these files are listed in Coordinated Universal Time (UTC). When you view the file information, it is converted to local time. To find the difference between UTC and local time, use the Time Zone tab in the Date and Time item in Control Panel.

Windows Vista and Windows Server 2008 file information notes

• The files that apply to a specific product, milestone (RTM, SPn), and service branch (LDR, GDR) can be identified by examining the file version numbers as shown in the following table.

  Version	Product	Milestone	Service branch
  6.0.6000.16xxx	Windows Vista	RTM	GDR
  6.0.6000.20xxx	Windows Vista	RTM	LDR
  6.0.6001.18xxx	Windows Vista SP1 and Windows Server 2008 SP1	SP1	GDR
  6.0.6001.22xxx	Windows Vista SP1 and Windows Server 2008 SP1	SP1	LDR

• Service Pack 1 is integrated into Windows Server 2008. Therefore, RTM milestone files apply only to Windows Vista. RTM milestone files have a 6.0.0000.xxxxxx version number.
• The .manifest files and the .mum files that are installed in each environment are listed separately in the "Additional file information for Windows Server 2008 and for Windows Vista" section. These files and their associated .cat (security catalog) files are critical to maintaining the state of the updated component. The .cat files are signed with a Microsoft digital signature. The attributes of these security files are not listed.

For all supported x86-based versions of Windows Server 2008 and Windows Vista

For all supported x64-based versions of Windows Server 2008 and Windows Vista

For all supported Itanium-based versions of Windows Server 2008

Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.

For more information about software update terminology, click the following article number to view the article in the Microsoft Knowledge Base:

Additional file information for Windows Vista and Windows Server 2008

Additional files for all supported x86-based versions of Windows Server 2008 and Windows Vista

Additional files for all supported x64-based versions of Windows Server 2008 and Windows Vista

Additional files for all supported Itanium-based versions of Windows Server 2008