Improved header comment with better instructions on the vfslog.c

extension.

FossilOrigin-Name: 4bd592c8f0e011e203443a6e88008a61d6926df5

diff --git a/ext/misc/vfslog.c b/ext/misc/vfslog.c
index 4854ca9a4cab29e22cf6b00ff4251667a4126b46..b55b06fcf3a7429bd9e78efbb5ec3d9f3b3de892 100644 (file)
--- a/ext/misc/vfslog.c
+++ b/ext/misc/vfslog.c
@@ -16,14 +16,37 @@
 
 /*
 ** This module contains code for a wrapper VFS that causes a log of
-** most VFS calls to be written into a file on disk. The log 
-** is stored as comma-separated variables.
+** most VFS calls to be written into a file on disk.
 **
-** All calls on sqlite3_file objects are logged.
-** Additionally, calls to the xAccess(), xOpen(), and xDelete()
-** methods are logged. The other sqlite3_vfs object methods (xDlXXX,
-** xRandomness, xSleep, xCurrentTime, xGetLastError and xCurrentTimeInt64) 
-** are not logged.
+** Each database connection creates a separate log file in the same
+** directory as the original database and named after the original
+** database.  A unique suffix is added to avoid name collisions.  
+** Separate log files are used so that concurrent processes do not
+** try to write log operations to the same file at the same instant, 
+** resulting in overwritten or comingled log text.
+**
+** Each individual log file records operations by a single database
+** connection on both the original database and its associated rollback
+** journal.
+**
+** The log files are in the comma-separated-value (CSV) format.  The
+** log files can be imported into an SQLite database using the ".import"
+** command of the SQLite command-line shell for analysis.
+**
+** One technique for using this module is to append the text of this
+** module to the end of a standard "sqlite3.c" amalgamation file then
+** add the following compile-time options:
+**
+**     -DSQLITE_EXTRA_INIT=sqlite3_register_vfslog
+**     -DSQLITE_USE_FCNTL_TRACE
+**
+** The first compile-time option causes the sqlite3_register_vfslog()
+** function, defined below, to be invoked when SQLite is initialized.
+** That causes this custom VFS to become the default VFS for all
+** subsequent connections.  The SQLITE_USE_FCNTL_TRACE option causes
+** the SQLite core to issue extra sqlite3_file_control() operations
+** with SQLITE_FCNTL_TRACE to give some indication of what is going
+** on in the core.
 */
 
 #include "sqlite3.h"

diff --git a/manifest b/manifest
index 3a2cbdcefc4fc43fa918a4327327fc6551957611..9a49cfa35ddbeff3c5a82e87566b7deda39cc2e7 100644 (file)
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Fix\sa\sbug\scausing\san\s"malformed\sdatabase\sschema\serror"\serror\sif\sa\stemp\stable\swith\sthe\ssame\sname\sas\san\sexisting\stable\sthat\shas\sat\sleast\sone\stemp\strigger\sattached\sto\sit\sis\screated.
-D 2013-10-19T15:07:49.621
+C Improved\sheader\scomment\swith\sbetter\sinstructions\son\sthe\svfslog.c\nextension.
+D 2013-10-19T16:51:39.506
 F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
 F Makefile.in 0522b53cdc1fcfc18f3a98e0246add129136c654
 F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
@@ -116,7 +116,7 @@ F ext/misc/regexp.c af92cdaa5058fcec1451e49becc7ba44dba023dc
 F ext/misc/rot13.c 1ac6f95f99b575907b9b09c81a349114cf9be45a
 F ext/misc/spellfix.c 5e1d547e9a2aed13897fa91bac924333f62fd2d9
 F ext/misc/totype.c 4a167594e791abeed95e0a8db028822b5e8fe512
-F ext/misc/vfslog.c db244ca9e64d5e036499c81806a5aabf23695b77
+F ext/misc/vfslog.c fe40fab5c077a40477f7e5eba994309ecac6cc95
 F ext/misc/vtshim.c babb0dc2bf116029e3e7c9a618b8a1377045303e
 F ext/misc/wholenumber.c 784b12543d60702ebdd47da936e278aa03076212
 F ext/rtree/README 6315c0d73ebf0ec40dedb5aa0e942bc8b54e3761
@@ -1126,7 +1126,7 @@ F tool/vdbe-compress.tcl f12c884766bd14277f4fcedcae07078011717381
 F tool/warnings-clang.sh f6aa929dc20ef1f856af04a730772f59283631d4
 F tool/warnings.sh d1a6de74685f360ab718efda6265994b99bbea01
 F tool/win/sqlite.vsix 030f3eeaf2cb811a3692ab9c14d021a75ce41fff
-P e801f35a96d861a1e5f223655af4c8a6a7e356bc
-R ac49857d368ae5ae24a9a42091be2bd4
-U dan
-Z 1c112f168e833ab0ddaf48bcba202dcf
+P 56dca4a65c3b14123272fa0cc5c15530c06fda28
+R 1cee309be53ed4b90f763a6791fd81dc
+U drh
+Z 23f623447e2329bbecfcb9fee8496fa4

diff --git a/manifest.uuid b/manifest.uuid
index 38fbe878acadcb5e5f0501153433f20d18f1be6c..dd2fc699855a825a7e99b54cddd1dd1dab9b9134 100644 (file)
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-56dca4a65c3b14123272fa0cc5c15530c06fda28
\ No newline at end of file
+4bd592c8f0e011e203443a6e88008a61d6926df5
\ No newline at end of file