Merge pull request #119 from QB64Team/fix-seek-eof

Fix EOF not being reset after SEEK is used.

internal/c/libqb.cpp

@@ -23337,6 +23337,10 @@ void sub_put2(int32 i,int64 offset,void *element,int32 passed){
                     f->file_handle->seekp(position);
                 }
                 f->pos=position;
+                if (f->pos<=gfs_lof(i)){
+                    f->eof_passed=0;
+                    f->eof_reached=0;
+                }
                 return 0;
             #endif
             
@@ -23351,6 +23355,10 @@ void sub_put2(int32 i,int64 offset,void *element,int32 passed){
                     }
                 }
                 f->pos=position;
+                if (f->pos<=gfs_lof(i)){
+                    f->eof_passed=0;
+                    f->eof_reached=0;
+                }
                 return 0;
             #endif
             

internal/help/$IF.txt

@@ -14,9 +14,15 @@
 * $IF is the start of a precompiler code block which includes or excludes sections of code from being compiled.
 * There is no single line $IF statement.  $IF must be in a valid $IF THEN...$END IF block to work properly.
 * Like all other metacommands, you can not use more than one metacommand per line. '''Use of : to separate statements in a single line is not allowed.'''
-* Variable names can contain numbers, letters, and periods -- in any order.
-* Expressions can contain one set of leading and/or trailing quotes; and any number of numbers, letters, and periods, in any order.
-* The precompiler comes with some preset values which can be used to help determine which code blocks to include/exclude.  These are: '''WIN''' or '''WINDOWS''' if the user is running QB64 in a Windows environment.  '''LINUX''' if the user is running QB64 in a Linux environment.  '''MAC''' or '''MACOSX''' if the user is running QB64 in a macOS environment.  '''32BIT''' if the user is running a 32-bit version of QB64.  '''64BIT''' if the user is running a 64-bit version of QB64.
+* Variable names can contain numbers, letters and periods, in any order.
+* Expressions can contain one set of leading and/or trailing quotes; and any number of numbers, letters and periods, in any order.
+* The precompiler comes with some preset values which can be used to help determine which code blocks to include/exclude.  These are:
+** '''WIN''' or '''WINDOWS''' if the user is running QB64 in a Windows environment.
+** '''LINUX''' if the user is running QB64 in a Linux environment.
+** '''MAC''' or '''MACOSX''' if the user is running QB64 in a macOS environment.
+** '''32BIT''' if the user is running a 32-bit version of QB64.
+** '''64BIT''' if the user is running a 64-bit version of QB64.
+** '''VERSION''', which is set to the version of the QB64 compiler. This is a number and can be ordered, see example below.
 * [[$END IF]] denotes the end of a valid precompiler $IF block.
 * [[$ELSEIF]] must follow a valid $IF or $ELSEIF statement.
 * If [[$ELSE]] is used, it must be used as the last conditional check before $END IF.  $ELSEIF cannot come after $ELSE.
@@ -58,8 +64,19 @@ The [[$LET]] and $IF statements let the programmer control the code that actuall
 ''Explanation:'' For the above, the CONST slash is defined by the automatic internal flags which returns what operating system is being used at compile time. On a Windows PC, the Slash will be the backslash; for any other OS it will be the forward slash.
 
 
+''Example 3:''
+{{CodeStart}} '' ''
+{{Cl|$IF}} VERSION < 1.5 THEN
+    {{Cl|$ERROR}} Requires QB64 version 1.5 or greater
+{{Cl|$END IF}}
+{{CodeEnd}}
+
+''Explanation:'' VERSION is a predefined variable that holds the QB64 compiler version. If we know our program needs features only available above a certain version, we can check for that and give the user a helpful error message instead of a confusing error elsewhere in the program.
+
+
 {{PageSeeAlso}}
 * [[$LET]]
+* [[$ERROR]]
 * [[Metacommand]]s
 
 

internal/help/Keyword_Reference_-_Alphabetical.txt

@@ -142,6 +142,7 @@ __NOTOC__
 * [[$ELSE]] (Pre-Compiler [[Metacommand]]) {{text|used in conjunction with $IF for the precompiler.}}
 * [[$ELSEIF]] (Pre-Compiler [[Metacommand]]) {{text|used in conjunction with $IF for the precompiler.}}
 * [[$END IF]] (Pre-Compiler [[Metacommand]]) {{text|used in conjunction with $IF for the precompiler.}}
+* [[$ERROR]]  (Pre-Compiler [[Metacommand]]) {{text|used to trigger compiler errors.}}
 * [[_ERRORLINE]] (function) {{text|returns the source code line number that caused the most recent runtime error.}}
 * [[_ERRORMESSAGE$]] (function) {{text|returns a human-readable message describing the most recent runtime error.}}
 * [[$EXEICON]] (Pre-Compiler [[Metacommand]]) {{text|used with a .ICO icon file name to embed the image into the QB64 executable.}}

internal/help/Keyword_Reference_-_By_usage.txt

@@ -657,6 +657,7 @@ The following table describes the error codes that are reported by the '''QB64''
  
 * [[$CHECKING]]:OFF/ON {{text|(QB64 only) turns event and error checking ON and OFF. ON (default) can only be used after it is OFF.}}
 * [[$CONSOLE]] {{text|creates a console window throughout the program.}}
+* [[$ERROR]]  (Pre-Compiler [[Metacommand]]) {{text|used to trigger compiler errors.}}
 * [[$SCREENHIDE]] {{text|hides the program window throughout the program until [[$SCREENSHOW]] is used.}}
 * [[$SCREENSHOW]] {{text|displays the main program window throughout the program only after [[$SCREENHIDE]] or [[_SCREENHIDE]] has been used.}}
 

internal/help/Metacommand.txt

@@ -36,6 +36,8 @@
 
 :[[$IF]]...[[$END IF]] 'precompiler directive
 
+: [[$ERROR]] MESSAGE 'trigger a compilation error, useful inside $IF blocks
+
 
 ===Description===
 * [[$INCLUDE]] can be used at the beginning or at the end of program SUB procedures.
@@ -44,6 +46,7 @@
 * [[$RESIZE]]:ON allows a user to resize the program window. OFF is default.
 * [[$SCREENHIDE]] hides the QB64 program window throughout the program until [[$SCREENSHOW]] is used.
 * [[$IF]]...[[$END IF]] allows selective inclusion of code in the final program.
+* [[$ERROR]] MESSAGE causes a compilation error whenever QB64 attempts to compile it, displaying MESSAGE to the user. This is useful if inside a $IF block, as the error can be conditional.
 * '''Do not comment out with ' or [[REM]] QB64-specific metacommands.'''
 
 

internal/help/_MEM.txt

@@ -28,22 +28,23 @@ END TYPE
 :: ''name'''''.TYPE''' is the type (represented as bits combined to form a value) AS [[_OFFSET]]:
 
 ==.TYPE values ==
-:::* 0 = UDT ([[TYPE|user defined type]]) or memory created by [[_MEMNEW]]
-:::* 1 = 1 bit   ELEMENT.SIZE=1   *Only used along with specific types (currently integers or floats)
-:::* 2 = 2 bit. ELEMENT.SIZE=2   *
-:::* 4 = 4 bit. ELEMENT.SIZE=4   *
-:::* 8 = 8 bit. ELEMENT.SIZE=8   *
-:::* 16 = 16 bit. ELEMENT.SIZE=16  *
-:::* 32 = 32 bit. ELEMENT.SIZE=32  *
-:::* 64 = 64 bit. ELEMENT.SIZE=64  *
-:::* 128 = 128 bit. ELEMENT.SIZE=128 *
-:::* 256 = 256 bit. ELEMENT.SIZE=256 *
-:::* 512(+ bit*) = integer types only(ie. whole numbers)
-:::* 1024(+ bit*) = floating point types only(ie. numbers that can have a decimal point)
-:::* 2048 = [[STRING]] type only
-:::* 4096(+ 512 + bit*) = [[_UNSIGNED]] integer type only
-:::* 8192 = [[_MEM]] type only
-:::* 16384(+ 512 + bit*)= [[_OFFSET]] type only
+:::* [bit 0] 1* byte types (_BYTE)
+:::* [bit 1] 2* byte types (INTEGER)
+:::* [bit 2] 4* byte types (LONG or SINGLE)
+:::* [bit 3] 8* byte types (DOUBLE or _INTEGER64)
+:::* [bit 4] 16* byte types (reserved for future use)
+:::* [bit 5] 32* byte types (_FLOAT)
+:::* [bit 6] 64* byte types (reserved for future use)
+:::* [bit 7] 128 = integer types (_BYTE, INTEGER, LONG, _INTEGER64) (added to *)
+:::* [bit 8] 256 = floating point types (SINGLE, DOUBLE, _FLOAT) (added to *)
+:::* [bit 9] 512 = STRING types (fixed length or variable length)
+:::* [bit 10] 1024 = _UNSIGNED types (added to *+128)
+:::* [bit 11] 2048 = pixel data usually from _MEMIMAGE (added to 1+128+1024 for 256 color screens, or 2+128+1024 for text screens, or 4+128+1024 for 32-bit color screens)
+:::* [bit 12] 4096 = _MEM TYPE structure (NOT added to 32768)
+:::* [bit 13] 8192 = _OFFSET type (added to 4+128+[1024] or 8+128+[1024] or future_size+128+[1024])
+:::* [bit 14] 16384 = data created/defined by _MEMNEW(size) or _MEMNEW(offset,size)
+:::* [bit 15] 32768 = a custom, user defined type (ie. created with TYPE name ... END TYPE)
+:::* [bit 16] 65536 = an array of data (added to other type values defining the array's data type)
 ''Note: If a future integer, float or other type doesn't have a size that is 1,2,4,8,16,32,64,128 or 256 it won't have a size-bit set.''
 
 * '''Note: [[_OFFSET]] values cannot be cast to other variable [[Variable Types|type]]s reliably. _MEM is a reserved custom variable [[Variable Types|type]].'''

internal/help/links.bin

@@ -87,6 +87,7 @@ _ECHO,_ECHO
 $ELSE,$ELSE
 $ELSEIF,$ELSEIF
 $END,$END IF
+$ERROR,$ERROR
 _ERRORLINE,_ERRORLINE
 _ERRORMESSAGE$,_ERRORMESSAGE$
 $EXEICON,$EXEICON