i noticed there is a difference between Word and Wordpad opening .doc files.
my file system filter driver can see the IRP_MJ_READ irps from Word but not
one from Wordpad requesting for the file contents.
is there any other way that Wordpad is reading documents?
@@
<" )~ Be yourself…
//\ Ho Mun Chuen
You should at least see one IRP_MJ_READ.
Worpad maps the file in memory so the remainder Reads may come
through FastIO.
In my system (NT4.0ServerSP4) Worpad generates two IRP_MJ_READ per file.
Inaki.
-----Original Message-----
From: Ho Mun Chuen
Sent: jueves 24 de febrero de 2000 6:01
To: File Systems Developers Interest List
Subject: [ntfsd] Word and Wordpadi noticed there is a difference between Word and Wordpad opening .doc
files.
my file system filter driver can see the IRP_MJ_READ irps from Word but
not
one from Wordpad requesting for the file contents.is there any other way that Wordpad is reading documents?
@@
<" )~ Be yourself…
//\ Ho Mun Chuen
You are currently subscribed to ntfsd as: xxxxx@pandasoftware.es
To unsubscribe send a blank email to $subst(‘Email.Unsub’)
i do see some reads for small sizes like 2 bytes, 4 bytes, 8 bytes, etc
starting from offset 0 but not anything larger than 8 bytes. i have sort of
disabled FastIo by returning FALSE so that IRP_MJ_READs would be used
instead all along. well, what i did extra was to add a header to the files
and would offset any reads or writes with the length of this header before
sending it down, after which in the completion routine i would reset it back
to what it was supposed to reflect. *sigh*, this works for Notepad and Word
but not Wordpad… i always thought Word would be a more difficult
application to handle…
@@
<" )~ Be yourself…
//\ Ho Mun Chuen
----- Original Message -----
From: I?aki Castillo
To: File Systems Developers Interest List
Sent: Thursday, February 24, 2000 6:28 PM
Subject: [ntfsd] RE: Word and Wordpad
You should at least see one IRP_MJ_READ.
Worpad maps the file in memory so the remainder Reads may come
through FastIO.
In my system (NT4.0ServerSP4) Worpad generates two IRP_MJ_READ per file.
Inaki.
> -----Original Message-----
> From: Ho Mun Chuen
> Sent: jueves 24 de febrero de 2000 6:01
> To: File Systems Developers Interest List
> Subject: [ntfsd] Word and Wordpad
>
> i noticed there is a difference between Word and Wordpad opening .doc
> files.
> my file system filter driver can see the IRP_MJ_READ irps from Word but
> not
> one from Wordpad requesting for the file contents.
>
> is there any other way that Wordpad is reading documents?
>
> @@
> <" )~ Be yourself…
> //\ Ho Mun Chuen
>
>
>
> —
> You are currently subscribed to ntfsd as: xxxxx@pandasoftware.es
> To unsubscribe send a blank email to $subst(‘Email.Unsub’)
—
You are currently subscribed to ntfsd as: xxxxx@pmail.ntu.edu.sg
To unsubscribe send a blank email to $subst(‘Email.Unsub’)
>to what it was supposed to reflect. *sigh*, this works for Notepad and Word
but not Wordpad… i always thought Word would be a more difficult
Looks like WordPad uses memory-mapped files to open the document.
Max
> Worpad maps the file in memory so the remainder Reads may come
through FastIO.
Page faults of memory mapped file NEVER go via FastIO - they always go
via IRP.
Max
You can write a simple test app:
hFile = CreateFile(pszFile,
GENERIC_READ,
FILE_SHARE_READ,
NULL,
OPEN_EXISTING,
FILE_ATTRIBUTE_NORMAL,
NULL);
if (hFile != INVALID_HANDLE_VALUE) {
if ((ulSize = GetFileSize(hFile, NULL)) > 0) {
hFileMap = CreateFileMapping(hFile, NULL,
PAGE_READONLY, 0, 0, NULL);
if (hFileMap != NULL) {
lpvFile =
MapViewOfFile(hFileMap,dwMapDesired, 0, 0, 0);
if (lpvFile != NULL) {
// Copy some data from lpvFile
to a temporary buffer
UnmapViewOfFile(lpvFile);
}
CloseHandle(hFileMap);
}
}
CloseHandle(hFile );
}
and compare the data with the data you get by CreateFile + ReadFile.
This simple app ilustrates majority of problems with metadata stored
at the beginning of the file. I hope it also answer your question
about Word and WordPad.
Bests regards
mari
-----Original Message-----
From: Ho Mun Chuen [mailto:xxxxx@pmail.ntu.edu.sg]
Sent: Thursday, February 24, 2000 12:11 PM
To: File Systems Developers Interest List
Subject: [ntfsd] RE: Word and Wordpad
i do see some reads for small sizes like 2 bytes, 4 bytes, 8 bytes,
etc
starting from offset 0 but not anything larger than 8 bytes. i have
sort of
disabled FastIo by returning FALSE so that IRP_MJ_READs would be used
instead all along. well, what i did extra was to add a header to the
files
and would offset any reads or writes with the length of this header
before
sending it down, after which in the completion routine i would reset
it back
to what it was supposed to reflect. *sigh*, this works for Notepad and
Word
but not Wordpad… i always thought Word would be a more difficult
application to handle…
@@
<" )~ Be yourself…
//\ Ho Mun Chuen
----- Original Message -----
From: Inaki Castillo
To: File Systems Developers Interest List
Sent: Thursday, February 24, 2000 6:28 PM
Subject: [ntfsd] RE: Word and Wordpad
You should at least see one IRP_MJ_READ.
Worpad maps the file in memory so the remainder Reads may come
through FastIO.
In my system (NT4.0ServerSP4) Worpad generates two IRP_MJ_READ per
file.
Inaki.
> -----Original Message-----
> From: Ho Mun Chuen
> Sent: jueves 24 de febrero de 2000 6:01
> To: File Systems Developers Interest List
> Subject: [ntfsd] Word and Wordpad
>
> i noticed there is a difference between Word and Wordpad opening
.doc
> files.
> my file system filter driver can see the IRP_MJ_READ irps from Word
but
> not
> one from Wordpad requesting for the file contents.
>
> is there any other way that Wordpad is reading documents?
>
> @@
> <" )~ Be yourself…
> //\ Ho Mun Chuen
>
>
>
> —
> You are currently subscribed to ntfsd as: xxxxx@pandasoftware.es
> To unsubscribe send a blank email to $subst(‘Email.Unsub’)
—
You are currently subscribed to ntfsd as: xxxxx@pmail.ntu.edu.sg
To unsubscribe send a blank email to $subst(‘Email.Unsub’)
—
You are currently subscribed to ntfsd as: xxxxx@decros.cz
To unsubscribe send a blank email to $subst(‘Email.Unsub’)