Last update: 2008.07.01

• Overview
• Features
• Download
• DbgPrintLog manual
• EchoDbg manual
• Debugger extension manual
• Registry settings for DbgPrint logger (driver)
• SDK for DbgPrint logger
• KdPrint()/DbgPrint()/OutputDebugString()
• History

This utility is intended for catching debug messages going through DbgPrint() (also known as KdPrint() macro) and OutputDebugString(). It can write cathed messages to file and/or store them in memory for further crash dump analysis. When logs arecorded in file, you can view them with any text file viewer. Has a number of settings and can be reconfigured from keyboard without restart.

More detailed information you can find in DbgPrintLog manual

• Catch both Kernel mode KdPrint()/DbgPrint() and User mode OutputDebugString().
• Unlimited amount of captured logs.
• Is very fast. Performance doesn't depend on amount of already captured logs.
• Can accumulate logs on target machine. You can download them later with Kernel Debugger extension. This option is indispensable for debugging time-critical code and for capturing large amounts of logs. It saves a lot of time.
• Manageable process information and timestamp format (e.g. high-precision timer - 100ns).
• Automatic log rotation.
• syslog (RFC-3164) support.
• Fault-less capturing DbgPrint() on IRQL > DISPATCH_LEVEL.
• Boot-time log capturing. Doesn't require operator intervention.
• Kernel Debugger extension for extraction logs from live machine during remote debug session over COM, IEEE1394 or USB2.0 or from crashdump.
• SDK

DbgPrintLog utility was tested under the following OSes with enabled and with disabled SoftIce:

NT 3.51
NT 4.0               build 1381 Service Pack 4
NT 4.0               build 1381 Service Pack 6
NT 4.0               build 1381 Service Pack 6a
NT 4.0 (TS)          build 1381 Service Pack 6
NT 5.0 (Win 2000)    build 2195
NT 5.0 (Win 2000)    build 2195 Service Pack 2
NT 5.0 (Win 2000)    build 2195 Service Pack 4
NT 5.1 (Win XP)      build 2600 Service Pack 1, v.1081
NT 5.1 (Win XP)      build 2600 Service Pack 2, v.2055
NT 5.1 (Win XP)      build 2600 Service Pack 2
NT 5.2 (Win 2003)    build 3790
NT 5.2 (Win 2003-R2)            Service Pack 1
NT 6.0 (Vista)       

See also:

• KdPrint()/OutputDebugString() behavior
• WinDbg HOWTO for QA engineers