I am debugging a hangdump coming from a production server using WinDbg with the SoS extension.
There is a string parameter in one of the stacks, that I need to know the value of. However, it is a rather large string, and WinDbg won't print it when I am using DumpObj. This is the output from DumpObj:
0:036> !do 00000001b30d8668
Name: System.String
MethodTable: 0000064278436728
EEClass: 000006427803e520
Size: 5125300(0x4e34b4) bytes
(C:\WINDOWS\assembly\GAC_64\mscorlib\2.0.0.0__b77a5c561934e089\mscorlib.dll)
String: <String is invalid or too large to print>
Fields:
MT Field Offset Type VT Attr Value Name
000006427843d998 4000096 8 System.Int32 1 instance 2562638 m_arrayLength
000006427843d998 4000097 c System.Int32 1 instance 2562637 m_stringLength
0000064278438170 4000098 10 System.Char 1 instance 3c m_firstChar
0000064278436728 4000099 20 System.String 0 shared static Empty
>> Domain:Value 0000000000163260:000000007fff0370 00000000001a6760:000000007fff0370 <<
0000064278438020 400009a 28 System.Char[] 0 shared static WhitespaceChars
>> Domain:Value 0000000000163260:000000007fff0b60 00000000001a6760:000000007fff89f0 <<
How can I get the value of this string instance ? Preferably dumped to a file.
I would think twice before dumping 2562638 characters worth of text, but if you really want to, the text is stored following the fields of the string instance, so you can do a du <address+offset> <end address> to dump the actual text of the string. The output will look something like this:
00000000`132ab050 "this is an extremely long string"
00000000`132ab090 " of text, so don't even bother t"
00000000`132ab0d0 "o try to dump it to the screen -"
By logging the session output to a file, you can easily capture the output and do whatever post-processing you need.