Clarify the documentation on the nByte parameter to sqlite3_prepare().

Make it clear that nByte is a maximum string length.  Ticket #2516. (CVS 4162)

FossilOrigin-Name: d1ae3de4613d36b5352eb852f1951a09d4a92ac1

manifest

@@ -1,5 +1,5 @@
-C Get\sthe\smin/max\soptimization\sworking\swith\sdescending\sindices.\s\sTicket\s#2514.\s(CVS\s4161)
-D 2007-07-18T18:17:12
+C Clarify\sthe\sdocumentation\son\sthe\snByte\sparameter\sto\ssqlite3_prepare().\nMake\sit\sclear\sthat\snByte\sis\sa\smaximum\sstring\slength.\s\sTicket\s#2516.\s(CVS\s4162)
+D 2007-07-19T12:41:40
 F Makefile.in 0c0e53720f658c7a551046442dd7afba0b72bfbe
 F Makefile.linux-gcc 65241babba6faf1152bf86574477baab19190499
 F README 9c4e2d6706bdcc3efdd773ce752a8cdab4f90028
@@ -107,7 +107,7 @@ F src/random.c 6119474a6f6917f708c1dee25b9a8e519a620e88
 F src/select.c 3b167744fc375bddfddcef87feb18f5171737677
 F src/server.c 087b92a39d883e3fa113cae259d64e4c7438bc96
 F src/shell.c e7534cce78398bc1cac4a643e931fc6221c2897e
-F src/sqlite.h.in bbcc5481af9f40ce5762c323cf555581a025f3de
+F src/sqlite.h.in 8164526b1658a6dad472953ea91239849f913d45
 F src/sqlite3ext.h 95575e0d175a0271fe2c3232c0d11e8720ed6887
 F src/sqliteInt.h 81183ae71162818bf60478e738ff68604128bb06
 F src/sqliteLimit.h f14609c27636ebc217c9603ade26dbdd7d0f6afa
@@ -518,7 +518,7 @@ F www/tclsqlite.tcl 8be95ee6dba05eabcd27a9d91331c803f2ce2130
 F www/vdbe.tcl 87a31ace769f20d3627a64fa1fade7fed47b90d0
 F www/version3.tcl 890248cf7b70e60c383b0e84d77d5132b3ead42b
 F www/whentouse.tcl fc46eae081251c3c181bd79c5faef8195d7991a5
-P 7ef2aaf72a8a953df7a763dd94657bb4ff05294f
-R ff608d553175a9b0892b61edd3a60768
+P a80a3c9d0a5e0a8a3d67bd841e2076893fd5e9aa
+R d4afa784234874caf7b671e3a6ed87c3
 U drh
-Z 2ad3f38523c32921466d9249c05ca115
+Z c86e52f36ab4239de550f9e1ef291098

manifest.uuid

@@ -1 +1 @@
-a80a3c9d0a5e0a8a3d67bd841e2076893fd5e9aa
+d1ae3de4613d36b5352eb852f1951a09d4a92ac1

src/sqlite.h.in

@@ -30,7 +30,7 @@
 ** the version number) and changes its name to "sqlite3.h" as
 ** part of the build process.
 **
-** @(#) $Id: sqlite.h.in,v 1.217 2007/06/27 15:53:35 danielk1977 Exp $
+** @(#) $Id: sqlite.h.in,v 1.218 2007/07/19 12:41:40 drh Exp $
 */
 #ifndef _SQLITE3_H_
 #define _SQLITE3_H_
@@ -963,10 +963,14 @@ typedef struct sqlite3_stmt sqlite3_stmt;
 ** The second argument "zSql" is the statement to be compiled, encoded
 ** as either UTF-8 or UTF-16.  The sqlite3_prepare() and sqlite3_prepare_v2()
 ** interfaces uses UTF-8 and sqlite3_prepare16() and sqlite3_prepare16_v2()
-** use UTF-16. If the next argument, "nBytes", is less
+** use UTF-16.
+**
+** If the nByte argument is less
 ** than zero, then zSql is read up to the first zero terminator.  If
-** "nBytes" is not less than zero, then it is the length of the string zSql
-** in bytes (not characters).
+** nByte is non-negative, then it is the maximum number of 
+** bytes read from zSql.  When nByte is non-negative, the
+** zSql string ends at either the first '\000' character or 
+** until the nByte-th byte, whichever comes first.
 **
 ** *pzTail is made to point to the first byte past the end of the first
 ** SQL statement in zSql.  This routine only compiles the first statement
@@ -1019,28 +1023,28 @@ typedef struct sqlite3_stmt sqlite3_stmt;
 int sqlite3_prepare(
   sqlite3 *db,            /* Database handle */
   const char *zSql,       /* SQL statement, UTF-8 encoded */
-  int nBytes,             /* Length of zSql in bytes. */
+  int nByte,              /* Maximum length of zSql in bytes. */
   sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
   const char **pzTail     /* OUT: Pointer to unused portion of zSql */
 );
 int sqlite3_prepare_v2(
   sqlite3 *db,            /* Database handle */
   const char *zSql,       /* SQL statement, UTF-8 encoded */
-  int nBytes,             /* Length of zSql in bytes. */
+  int nByte,              /* Maximum length of zSql in bytes. */
   sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
   const char **pzTail     /* OUT: Pointer to unused portion of zSql */
 );
 int sqlite3_prepare16(
   sqlite3 *db,            /* Database handle */
   const void *zSql,       /* SQL statement, UTF-16 encoded */
-  int nBytes,             /* Length of zSql in bytes. */
+  int nByte,              /* Maximum length of zSql in bytes. */
   sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
   const void **pzTail     /* OUT: Pointer to unused portion of zSql */
 );
 int sqlite3_prepare16_v2(
   sqlite3 *db,            /* Database handle */
   const void *zSql,       /* SQL statement, UTF-16 encoded */
-  int nBytes,             /* Length of zSql in bytes. */
+  int nByte,              /* Maximum length of zSql in bytes. */
   sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
   const void **pzTail     /* OUT: Pointer to unused portion of zSql */
 );