Microsoft(R) Macro Assembler Package Version 5.10 Copyright 1988, Microsoft Corporation Text files on the Macro Assembler disks are tabbed to save disk space. If your printer does not automatically handle tabs during printing, you must use a print program that expands tabs. For example, use the DOS PRINT program to print this and other document or source files on the disk. The Microsoft Macro Assembler (MASM) Mixed-Language Support for Variables and Procedures --------------------------------------------------- All EXTRN, PUBLIC, and PROC items, as well as uses of the .MODEL directive, support a language type. The language type of EXTRN and PUBLIC variables determine whether or not an underscore is prefixed to the name (an underscore is prefixed only for variables with a C language type), and the language type of a procedure determines its calling and naming conventions. For an explanation of calling and naming conventions, see the Microsoft Mixed-Language Programming Guide. The language type consists of the word "C" or "Pascal" and uses the following syntax (lowercase items are placeholders, and bracketed items are optional): EXTRN [<langtype>] <varname>:<type> PUBLIC [<langtype>] <varname> procName PROC [NEAR|FAR] [<langtype>] [USES <regs>,] <args> For example, the C and Pascal keywords are used correctly in the following example: .MODEL SMALL,C EXTRN Pascal DosOpen:FAR PUBLIC C myVar myOpen PROC Pascal fName:PTR, mode:WORD . . . myOpen ENDP EVEN and ALIGN Directives ------------------------- Padding for EVEN and ALIGN is now optimized. Data segments are padded with zeros. Code segments are padded with special two-byte NOP instructions where possible. The two-byte NOP consists of the instruction XCHG BX,BX (87 DB hexadecimal) which is executed faster than two one-byte NOP instructions. /B Option Ignored ----------------- The /B option is now ignored, because its effect is irrelevant, given the new file buffering mechanism. However, the option is still accepted for the purposes of compatibility. The PTR Operator ---------------- The PTR operator can be used to specify the size of a register indirect operand for a CALL or JMP instruction. However, the size cannot be specified with NEAR or FAR. Use WORD or DWORD instead. (In 80386 32-bit segments, use DWORD or FWORD.) Examples are shown below: ; 8086, 80826, or 80386 16-bit mode jmp WORD PTR [bx] ; Legal near jump call NEAR PTR [bx] ; Illegal near call call DWORD PTR [bx] ; Legal far call jmp FAR PTR [bx] ; Illegal far jump ; 80386 32-bit mode only jmp DWORD PTR [bx] ; Legal near jump call NEAR PTR [bx] ; Illegal near call call FWORD PTR [bx] ; Legal far call jmp FAR PTR [bx] ; Illegal far jump This limitation only applies to register indirect operands. NEAR or FAR can be applied to operands associated with labels. Examples are shown below: jmp NEAR PTR pointer[bx] ; Legal call FAR PTR location ; Legal Assembler Behavior Change ------------------------- Some errors and questionable practices that were ignored by earlier versions are now flagged as errors. As a result, existing source code may produce errors or warnings. The following are examples: - Labels defined only during pass 1 cause errors if used in expressions. - A CS ASSUME that changes from pass 1 to pass 2 causes an error. - Constants are now checked for type overflow. - Reserved words used as labels produce warnings. - The OFFSET operator used with a constant causes an error. The STACK Combine Type ---------------------- The description of the STACK combine type in Section 5.2.2.3 does not explain how multiple initialized stack segments are combined. The total size of the stack is the total size of all stack definitions. LINK puts initialized data for each defined stack segment at the end of the stack. Data initialized in the last segment linked override data initialized in previous segments. This behavior is usually not relevant, since most programs only define one stack of uninitialized data. Stack data cannot be initialized with simplified segment directives. Clarification of Parsing Error ------------------------------ The following error can be difficult to interpret because of the way the assembler parses (analyzes) source code: A2015: Symbol already different kind: <name> Typically, the assembler generates this error message when a symbol is used in a way inconsistent with how it was declared: for example, a symbol is declared as an external absolute but then used as a local code label. However, the assembler also generates this error when a symbol in the second source-code field can be interpreted as either an operation or an operand. The following example illustrates this problem: SYM1 MACRO structName, varName varName structName <> ENDM SYM2 STRUCT field1 DB field2 DW SYM2 ENDS SYM1 SYM2, <mylabel> The last line of code causes error A2015 to be generated. The assembler first looks at the second field of the line, which contains the symbol SYM2. Since SYM2 is a structure, the assembler considers SYM2 to be an operation rather than an operand, and therefore it considers SYM1 to be a label (rather than an operation). The way to avoid this error is simply code the instruction as: SYM1 <SYM2>, <mylabel> HIGH and LOW Operators ---------------------- The HIGH and LOW operators work reliably only with constants and with offsets to external symbols. HIGH and LOW operations are not supported for offsets to local symbols. Mixed-Mode Programming (386 Only) --------------------------------- When assembling code for .386 mode, the assembler now supports direct- addressing modes between segments with different USE sizes. (Segments can have the USE16 or USE32 attribute; these attributes refer to the default size of offsets.) Direct-addressing references to labels in other segments are correctly resolved. In the following example, the assembler correctly uses a 32-bit offset to access the data at label a32: .386 SEG32 SEGMENT USE32 a32 DD ? SEG32 ENDS SEG16 SEGMENT USE16 assume ds:seg32 mov eax,a32 SEG16 ENDS You can also execute a CALL or a JMP to a label in a segment with a different USE size. However, the label must be declared FAR, and the CALL or JMP must not be a forward reference. The following example shows the correct method for executing such a CALL or JMP: .386 COD16 SEGMENT USE16 'CODE' proc16 PROC FAR ret proc16 ENDP lab16 LABEL FAR COD16 ENDS COD32 SEGMENT USE32 'CODE' call proc16 jmp lab16 COD32 ENDS Additional Error Messages ------------------------- 19 Wrong type of register The register specified in the operand field was incompatible with the directive or instruction in the operation field. For example, the following instruction causes this error because you cannot increment the code segment: inc cs 36 Extra NOP inserted During pass 1 the assembler did not have enough information to correctly infer the length of the encoding for the instruction. During pass 2 the encoding was found to be shorter than the space allocated from pass 1, so one or more NOP instructions were inserted as padding. It may be possible to generate a smaller amount of code by eliminating a forward reference to a symbol. The Microsoft Cross-Reference Utility (CREF) New Feature ----------- Cross-reference listing files created with CREF now have an additional symbol. A line number followed by + indicates that a symbol is modified at the given line. For example: TST . . . . . . . . . . . . . . 134# 237 544+ The symbol TST is defined at line 134, used at line 237, and modified at line 544. The Mouse Driver If you use the Microsoft Mouse with the Microsoft CodeView(R) debugger you must have Version 6.0 or later of the Microsoft Mouse. If you do not, use the version of the MOUSE.COM driver provided in this package. Copy MOUSE.COM to the appropriate mouse directory. When you are ready to use the mouse, type mouse at the DOS command level. If you want to install the mouse driver automatically every time you reboot, insert the "mouse" command in your AUTOEXEC.BAT file. Note that in earlier releases of Microsoft C, both the MOUSE.SYS and the MOUSE.COM driver were provided. If you have been using an earlier version of the MOUSE.SYS driver, delete the following line from your CONFIG.SYS file: device=<directory>mouse.sys where <directory> is the directory where the earlier mouse driver resides. Microsoft CodeView Debugger New Command-Line Option ----------------------- If you have an IBM Personal System/2, then you can use the /50 command-line option to start the CodeView debugger in 50-line mode. Note that you must be in 25-line mode to effectively use either the /43 or /50 command-line option. CONFIG.SYS Setting for CVP -------------------------- To run the protected-mode CodeView debugger (CVP.EXE), you must have the following line in your CONFIG.SYS file: IOPL=YES Using the 7 Command in Protected Mode ------------------------------------- If you are using OS/2 protected mode and have a math coprocessor, then you need to use a patch before you can use the CVP 7 command. To apply the patch, use the OS2PATCH.EXE and PTRACE87.PAT files that come on the same disk that CVP.EXE comes on. You also need to locate the PATCH.EXE file that comes with OS/2 and make sure that this file is in a directory listed in your PATH environment variable. Then follow these steps: 1) Change the current drive and directory to the root directory of the boot disk. (If the boot disk is a floppy, make sure it is inserted in the drive you used to boot from.) 2) Give the following command line at the DOS prompt: OS2PATCH /A PTRACE87.PAT Note that you may need to give the complete path names for the OS2PATCH.EXE and for the PTRACE87.PAT file. You do not need to give a path name for the OS2PATCH.EXE file if you have placed this file in a directory listed in your PATH environment variable. Using the Real-Mode Debugger in the Compatibility Box ----------------------------------------------------- When running the real-mode CodeView debugger in the DOS 3.x compatibility box, start the debugger with the /S command-line option. Otherwise, the mouse pointer will not appear. Using the CodeView Debugger with BIND ------------------------------------- The real-mode CodeView debugger cannot debug bound (dual-mode) applications. However, the protected-mode CodeView debugger, CVP, can debug bound applications. Expression Evaluator for BASIC Programs --------------------------------------- In the BASIC expression evaluator, "+" is not supported for string concatenation. Stack Trace Command ------------------- In order for the Stack Trace command (or the Calls menu) to work reliably, you need to execute to at least the beginning of the main function or procedure, and the current module should have full CodeView information (a module has full CodeView information if compiled or assembled with /Zi). Error Messages -------------- The error message "? cannot display" indicates that the Display Expression command (?) has been passed a valid symbol that it cannot display. In previous versions of the debugger, structures could not be displayed. With current version of the debugger, only the enums type cannot be displayed. The error message "Expression not a memory address" occurs when the Tracepoint command is given without a symbol that evaluates to a single memory address. For example, the commands "TP?1" and "TP?a+b" each produce this error message. The proper way to put a tracepoint on the word at address 1 is with the command "TPW 1". The error message "Function call before 'main'" occurs when you attempt to evaluate a program-defined function before you have entered the main function. Execute to at least to the beginning of the main function before attempting to evaluate program-defined functions. The error message "Bad emulator info" occurs when CodeView cannot read data from the floating-point emulator. The error message "Floating point not loaded" has a special meaning for CVP (in addition to the explanation given in the CodeView and Utilities manual). Each thread has its own floating-point emulator. This message is issued when the current thread has not initialized its own emulator. Microsoft Pascal Programs ------------------------- In this release, Microsoft Pascal programs cannot be debugged with the CodeView debugger. Exit Codes for Utilities The exit codes for LINK and the utilities in the Microsoft CodeView and Utilities manual should appear as follows: LINK ---- Code Meaning 0 No error. 2 Program error--something was wrong with the commands or files input to the linker. 4 System error. The linker - ran out of space on output files - was unable to reopen the temporary file - experienced an internal error - was interrupted by the user LIB, EXEPACK, EXEMOD, MAKE, and SETENV --------------------------------------- Code Meaning 0 No error. 2 Program error--something was wrong with the commands or files input to the utility. 4 System error. The utility ran out of memory, was interrupted by the user, or experienced an internal error. Microsoft Overlay Linker (LINK) Overlay Restrictions -------------------- You cannot use long jumps (using the longjmp library function) or indirect calls (through a function pointer) to pass control to an overlay. When a function is called through a pointer, the called function must be in the same overlay or in the root. Changed LINK Error Messages --------------------------- The explanation for fatal-error message L1008 is changed as follows: The /SEGMENTS option specified a limit greater than 3072 on the number of segments allowed. Error message L1009 has been changed to read as follows: L1009 <number> : CPARMAXALLOC : illegal value Error message L1053 has been changed to read as follows: L1053 out of memory for symbol table The program had more symbolic information (such as public, external, segment, group, class, and file names) than the amount that could fit in available real memory. Try freeing memory by linking from the DOS command level instead of from a MAKE file or from an editor. Otherwise, combine modules or segments and try to eliminate as many public symbols as possible. Warning message L4050 has been changed as follows: L4050 too many public symbols for sorting The linker uses the stack and all available memory in the near heap to sort public symbols for the /MAP option. If the number of public symbols exceeds the space available for them, this warning is issued, and the symbols are not sorted in the map file but are listed in arbitrary order. New LINK Error Messages ----------------------- L1003 /QUICKLIB, /EXEPACK incompatible You cannot link with both the /QU option and the /E option. L1006 <option-text>: stack size exceeds 65535 bytes The value given as a parameter to the /STACKSIZE option exceeds the maximum allowed. L1063 out of memory for CodeView information The linker was given too many object files with debug information, and the linker ran out of space to store it. Reduce the number of object files that have debug information. L1115 /QUICKLIB, overlays incompatible You specified overlays and used the /QUICKLIB option. These cannot be used together. L2013 LIDATA record too large An LIDATA record contained more than 512 bytes. This is probably a compiler error. L2024 <name>: special symbol already defined Your program defined a symbol name that is already used by the linker for one of its own low-level symbols. (For example, the linker generates special symbols used in overlay support and other operations.) Choose another name for the symbol in order to avoid conflict. L2025 <segmentname>: segment with > 1 class name not allowed with /INC Your program defined a segment more than once, giving the segment different class names. Different class names for the same segment are not allowed when you link with the /INCREMENTAL option. Normally, this error should never appear unless you are programming with MASM. For example, if you give the two MASM statements _BSS segment 'BSS' and _BSS segment 'DATA' then the statements have the effect of declaring two distinct segments. ILINK does not support this situation, so it is disallowed when the /INCREMENTAL option is used. L2041 stack plus data exceed 64K The total of near data and requested stack size exceeds 64K, and the program will not run correctly. Reduce the stack size. The linker only checks for this condition if /DOSSEG is enabled, which is done automatically in the library startup module. L2043 Quick Library support module missing When creating a Quick library, you did not link with the required QUICKLIB.OBJ module. L2044 <name> : symbol multiply defined, use /NOE The linker found what it interprets as a public-symbol redefinition, probably because you have redefined a symbol that is defined in a library. Relink with the /NOEXTDICTIONARY (/NOE) option. If error L2025 results for the same symbol, then you have a genuine symbol-redefinition error. L4003 intersegment self-relative fixup at <offset> in segment <name> pos: <offset> Record type: 9C target external '<name>' The linker found an intersegment self-relative fixup. This error may be caused by compiling a small-model program with the /NT option. L4034 more than 239 overlay segments; extra put in root Your program designated more than the limit of 239 segments to go in overlays. Starting with the 234th segment, they are assigned to the root (that is, the permanently resident portion of the program). Microsoft Library Manager (LIB) New Option ---------- There is a new option for LIB: /NOIGNORECASE (abbreviated as /N). This option tells LIB to not ignore case when comparing symbols. names. By default, LIB ignores case. Multiple symbols that are the same except for case can be put in the same library. An example of this is: "_Open" and "_open". Normally you could not add both these symbols to the same library. Note that if a library is built with /NOI, the library is internally "marked" to indicate /NOI. All libraries built with earlier versions of LIB are not marked. If you combine multiple libraries, and any one of them is marked /NOI, then /NOI is assumed for the output library. In addition, LIB also supports the option /IGNORECASE (/I), which is completely analogous to /NOIGNORECASE. /I is the default. The only reason to use it would be if you have an existing library marked /NOI that you wanted to combine with other libraries which were not marked, and have the output library be not marked. If you don't use /IGNORECASE, the output is marked /NOI (see above). Changed LIB Error Messages -------------------------- Warning messages U4152, U4155, and U4157-U4159 for LIB are now nonfatal error messages U2152, U2155, and U2157-U2159, respectively. Warning message U4151 has been changed to read as follows: U4151 '<name>' : symbol defined in module <name>, redefinition ignored New LIB Error Messages ---------------------- The following new warning messages have been added for LIB: U4155 <modulename> : module not in library A module specified to be replaced does not already exist in the library. LIB adds the module anyway. U4157 insufficient memory, extended dictionary not created U4158 internal error, extended dictionary not created For the reason indicated, LIB could not create an extended dictionary. The library is still valid, but the linker is not able to take advantage of the extended dictionary to speed linking. Microsoft Program Maintenance Utility (MAKE) New Error Message ----------------- U1015: <file> : error redirection failed This error occurs if the /X option is given and error output cannot be redirected to the given file (for example, because the file is read-only). Inference Rules --------------- You cannot have inference rules in both the TOOLS.INI and the description file that use both the same inextension and outextension. For example, you cannot place the following inference rule in the TOOLS.INI file: .c.obj: cl /c /Zi /Od $*.c while also placing the following line in the description file: .c.obj: cl /Ot $*.c However, you can define the same macro in both the TOOLS.INI and the description file. In such cases, the definition in the description file takes precedence. Backslash () as Continuation Character --------------------------------------- Note that MAKE considers a backslash immediately followed by a new-line character to be a continuation character. When it finds this combination in a description file, MAKE concatenates the line immediately following the combination with the line where the combination appears. If you define a macro that ends in a backslash, make sure that you put a space after the terminating backslash. For example, if you want to define macros for the path C:SRCBIN and C:SRCLIB, you must use the format illustrated below: BINPATH=C:SRCBIN<space><newline> LIBPATH=C:SRCLIB<space><newline> To illustrate the problems that can result if you do not put a space before the new-line character, assume that the macros above appear as shown below instead: BINPATH=C:SRCBIN<newline> LIBPATH=C:SRCLIB<newline> Because a new-line character appears immediately after the backslash at the end of the first macro, MAKE assumes that you are defining the single macro shown below: BINPATH=C:SRCBINLIBPATH=C:SRCLIB Microsoft STDERR Redirection Utility (ERROUT) The ERROUT utility does not accept batch files. To redirect standard-error output from a batch file, you must enter a command of the following form: ERROUT COMMAND /c <batchcommand> If no /f option is given, then ERROUT redirects standard-error output to the standard-output device. Mixed-Language Programming Setting Up Calls to High-Level Languages ---------------------------------------- Section 6.6 of the Microsoft Mixed-Language Programming Guide gives in- structions for setting up a call to a high-level language from assembly language. Before you execute a call to a BASIC, Pascal, or FORTRAN routine, remember to declare an additional parameter if the return value is noninteger. This additional parameter must contain the offset address of the return value, for which you must allocate room within the stack segment (normally DGROUP, the same as the default data segment). The BIND Utility Specifying Libraries -------------------- You need to include DOSCALLS.LIB on the BIND command line. If DOSCALLS.LIB is not in the current directory, you must give the complete path name to DOSCALLS.LIB. BIND automatically searches for API.LIB by looking in directories listed in the LIB environment variable. However, if API.LIB is specified on the command line, then BIND will not check the LIB environment variable; instead, you will need to give the complete path name. For example, the following command line successfully uses BIND, if API.LIB is located in a directory listed in the LIB environment variable: BIND FOO.EXE LIBDOSCALLS.LIB Using BIND with Packed Files ---------------------------- The version of BIND released with this package does not work with files that have been linked with the /EXEPACK linker option. Running Bound Files with DOS 2.1 -------------------------------- A dual-mode executable file produced with BIND can be run in both DOS 3.x and DOS 2.x environments. However, if you change the name of an executable file produced by BIND, then it will not run under DOS 2.1. The Microsoft Incremental Linker (ILINK) ILINK Fatal Error Messages -------------------------- .sym seek error .sym read error The .SYM file is corrupted. Do a full link. If the error persists, contact Microsoft. .sym write error The disk is full or the .SYM file already exists with the READONLY attribute. map for segment <name> exceeds 64K The symbolic information associated with the given segment exceeds 64K bytes, which is more than ILINK can handle. can't ilink library <name> You tried to incrementally link an altered library. ILINK does not link .LIB files but only .OBJ files. Use a full link instead. .obj close error The operating system returned an error when ILINK attempted to close one of the .OBJ files. Do a full link. If the error persists, contact Microsoft. too many LNAMES in <modname> An object module has more than 255 LNAME records. too many SEGDEFs in <modname> The given object module has more than 100 SEGDEF records. too many GRPDEFs in <modname> The given object module has more than 10 GRPDEF records. symbol <name> multiply defined The given symbol is defined more than once. #3 Please report this error to Microsoft. Out of Memory ILINK ran out of memory for processing the input. If you are running ILINK under MAKE, try running it from the shell. Otherwise, do a full link. could not run exec ILINK was unable to find the file EXEC.EXE, which should be placed somewhere in the search path or in the current directory. .exe file too big, change alignment The segment sector alignment value in the .EXE file is too small to express the size of one of the segments. Do a full link and increase the alignment value with the /ALIGNMENT option to LINK. .ilk seek error The .ILK file is corrupted. Do a full link. If the error persists, contact Microsoft. Too many defined segments ILINK has a limit of 255 defined segments, which are segments defined in an object module as opposed to an executable segment. Reduce the number of segments if you want to use ILINK. too many library files ILINK has a limit of 32 runtime libraries (.LIB files). Reduce the number of libraries. too many modules ILINK has a limit of 1204 modules in a program. Reduce the number of modules. .ilk write error The disk is full, or else ILINK cannot write to the .SYM file because a .SYM file currently exists and has the READONLY attribute. file <name> does not exist ILINK was unable to open the given file. The file named was in the file list in the .ILK file. seek error on library A .LIB file was corrupted. Do a full link and check your .LIB files. library close error The operating system returned an error when ILINK attempted to close one of the .LIB files. Do a full link. If the error persists, contact Microsoft. error closing EXE file The operating system returned an error when ILINK attempted to close the .EXE file. Do a full link. If the error persists, contact Microsoft. Invalid module reference <module> The program makes a dynamic link reference to a dynamic link module which is not represented in the .EXE file. could not update time on <filename> The operating system returned an error when ILINK attempted to update the time on the given file. Possibly the file had the READONLY attribute set. invalid flag <flag> only one -e command allowed The ILINK command syntax is incorrect. User Abort The user issued CTRL+C or CTRL+BREAK. file <name> write protected The .EXE, .ILK, or .SYM file needed to be updated and has the READONLY attribute. Change attribute to READWRITE. file <name> missing One of the .OBJ files specified on the command line is missing. file <name> invalid .OBJ format file <name> has invalid <recordtype> record The given .OBJ file has an invalid format or one that is not recognized by ILINK. This may have been caused by a compiler or assembler. file <module> was not full linked An .OBJ file was specified as input to ILINK, which was not in the list of files in the original full link. LOBYTE seg-relative fixups not supported This error message should occur only with MASM files. See the Microsoft Macro Assembler 5.0 Programmer's Guide. This type of object module is not supported by ILINK. <number> undefined symbols The given number of symbols were referred to in fixups but never publicly defined in the program. Incremental Violations ---------------------- These errors cause a full link to occur if the -e option is used and -i is not used, else they are fatal errors: symbol <name> deleted A symbol was deleted from an incrementally-linked module. <modname> contains new SEGMENT A segment was added to the program. <modname> contains changed segment <name> The segment contribution (code or data which the module contributes to a segment) changed for the given module: it contributed to a segment it didn't previously contribute to, or a contribution was removed. <modname>'s segment <name> grew too big The given segment grew beyond the padding for the given module. <modname> contains new GROUP <name> A new group was defined, via the GROUP directive in assembly language or via the /ND C compiler option. <modname> redefines group <name> to include <name> The members of the given group changed. symbol <name> changed The given data symbol was moved. can't add new communal data symbol <name> A new communal data symbol was added as an uninitialized variable in C or with the COMM feature in MASM. communal variable <name> grew too big The given communal variable changed size too much. invalid symbol type for <name> A symbol which was previously code became data, or vice versa. too many COMDEFS too many EXTDEFS The limit on the total of COMDEF records (communal data variables) and EXTDEF records (external references) is 2000. invalid CodeView information in .EXE file The CodeView information found is invalid. <name> contains new Codeview symbolic info A module previously compiled without -Zi was compiled with -Zi. <name> contains new linnum info A module previously compiled without -Zi or -Zd was compiled with -Zi or -Zd. <name> contains new public CV info New information on public-symbol addresses was added. invalid .exe file The .EXE file is invalid. Make sure you are using an up-to-date linker. If the error persists, contact Microsoft. invalid .ilk file .ilk read error .ilk seek error The .ILK file is invalid. Make sure you are using an up-to-date linker. If the error persists, contact Microsoft. .SYM/.ILK mismatch The .SYM and .ILK files are out of sync. Make sure you are using an up-to-date linker. If the error persists, contact Microsoft. <libname> has changed The given library has changed. can't link 64K-length segments ILINK cannot handle segments greater than 65,535 bytes long. can't link iterated segments ILINK cannot handle programs linked with /EXEPACK. Entry table expansion not implemented The program call tree changed in such a way that ILINK could not handle it. file <name> does not exist The .EXE, .SYM, or .ILK files are missing. <name> has changed The given library module name has changed. ILINK Warning messages ---------------------- Fixup frame relative to an (as yet) undefined symbol - assuming ok See documentation for LINK error messages L4001 and L4002, in the Microsoft CodeView and Utilities manual. <name> contains TYPEDEFs - ignored <name> contains BLKDEFs - ignored The .OBJ file contains records no longer supported by Microsoft language compilers. old .EXE free information lost The free list in the .EXE file has been corrupted. The free list keeps track of "holes" of free space in the EXE file. These holes are made available when segments are moved to new locations. file <name> has no useful contribution The given module makes no contribution to any segment. Main entry point moved The program starting address changed. You may want to consider doing a full link. Microsoft Editor Installing the Editor --------------------- The Microsoft Editor does not come with an MESETUP program. Instead, run the setup program for the assembler. This program offers you choices about how to set up the editor. Keystroke Configurations ------------------------ Some of the keystroke configurations listed in Table A.2 of the Microsoft Editor User's Guide may need to be changed. In the Quick/WordStar configuration, the Sinsert function is assigned to ALT+INS, not CTRL+INS. In the BRIEF configuration, the Plines function is assigned to CTRL+Z, and the Refresh function is assigned to CTRL+]. In the EPSILON configuration, the Ppage function is assigned to PGDN, and the Sdelete function is assigned to DEL and CTRL+D. The Compile Function -------------------- The commands Arg streamarg Compile Arg textarg Compile each use the command specified by the extmake:text switch. The editor does not check the extension of the file name given as an argument, but instead uses the "text" extension. The streamarg or textarg replaces a %s in the command. These commands are typically used to invoke MAKE. The Setfile Function -------------------- The commands that use Setfile, along with a streamarg or textarg, accept a variety of input: either the name of a file, a file name with a wild-card character (* or ?), the name of a directory, or the name of a disk drive. File names can also include environment variables, such as $INIT. If the streamarg or textarg is a directory name, then the editor changes the current directory. If the argument is a drive name, then the editor changes the current drive. Environment variables are translated into directories to be searched for a file. For example, the following macro directs the editor to search the $INIT environment variable in order to find the tools.ini file: tools.ini := Arg "$INIT:tools.ini" Setfile tools.ini :ctrl+j Entering Strings in Macros -------------------------- When you enter a text argument directly, no characters have special meaning (except when the argument is interpreted as a regular expression). However, when you enter text as part of a macro, then strings inside of quotes are interpreted according to the C string format. This format uses a backslash followed by double quotes (") to represent double quotes and it uses two backslashes (\) to represent a single backslash. Therefore, to find the next occurrence of the string She wrote, "Here is a backslash: " you could use the following macro definition: findit := Arg "She wrote, "Here is a backslash: \ "" Psearch Note that to indicate a backslash for a regular expression that is also part of a macro definition, you must use four consecutive backslashes. Using Text Switches ------------------- The text switches extmake and readonly each take a special kind of syntax that allows you to specify drive, file name, base name, or file extension. The syntax consists of the characters: %|<letters>F where <letters> consists of any of the following: "p" for path, "d" for drive, "f" for file base name, or "e" for file extension. For example, if you are editing the file c:dir1sample.c, and you make the following switch assignment: extmake:c cl /Fod:%|pfF %|dfeF then each time you give the command <Arg><Compile>, the editor performs the following system-level command: cl /Fod:dir1sample c:sample.c The expression "%s" is equivalent to "%|feF" except that the former only works once, whereas the latter can appear any number of times in the extmake switch assignment. The expression "%|F" is equivalent to "%|dpfeF". The Filetab Switch ------------------ The filetab switch is a numeric switch that determines how the editor translates tabs when loading a file into memory. The value of the switch gives the number of spaces associated with each tab column. For example, the setting "filetab:4" assumes a tab column every 4 positions on each line. Every time the editor finds a tab character in a file, it loads the buffer with the number of spaces necessary to get to the next tab column. Depending on the value of the entab switch, the editor also uses the filetab switch to determine how to convert spaces into tabs when writing to a file. The default value of filetab is 8. Functions Callable by C Extensions ---------------------------------- The following list summarizes functions from the standard compact- memory-model library, which should work when called by a C-extension module. (The technique of programming C extensions is presented in Chapter 8 of the Microsoft Editor User's Guide.) The memory model of the extension is assumed to be /Asfu (small code pointers, far data pointers, and stack segment unequal to data segment). This list uses the function categories from Chapter 4 of the Microsoft C Optimizing Compiler Run-Time Library Reference (Version 4.0 or later.) Buffer Manipulation: All functions can be called. Character Classification and Conversion: All functions can be called. Data Conversion: All functions can be called except for strtod() Directory Control: All functions can be called except for getcwd() File Handling: All functions can be called. Low-Level I/O Routines: All functions can be called, but write() will not work in binary mode. Console and Port I/O: All functions can be called except for cgets() cprintf() cscanf() Searching and Sorting: All functions can be called except for qsort() String Manipulation: All functions can be called except for strdup() BIOS Interface: All functions can be called. MS-DOS Interface: All functions can be called except for int86() int86x() Time: All functions can be called except for ctime() gmtime() localtime() utime() Miscellaneous: All functions can be called except for assert() getenv() perror() putenv() _searchenv() Linking Extensions in Protected Mode -------------------------------------- To link C extension modules in protected mode, link with the object file EXTHDRP.OBJ, instead of the real-mode header EXTHDR.OBJ.
In this guide you will learn how to install MASM32 on a Windows 10 machine, and also how to modify the Path environment variable to use the MASM tools directly from the command prompt. By the end of the guide you will have an environment to start writing software in assembly.
Let’s begin.
Download MASM for Windows 10
The first thing you need to do is head over to the MASM32 SDK download page. Select a mirror and your download should begin.
Next open up the archive and extract the installer to your desktop.
Installing MASM on Windows 10
Double click on the installer. It will ask for administrator privileges. This application is deemed to be safe so you can safely press yes. After you have granted permissions you will see a dialog similar to the one below:
Click on the install icon on the top left and select the drive you want to use to install MASM. I will select my D: partition. MASM will install all the necessary files to the root directory of whatever partition you select.
Tip: I like to create a separate partition for my assembly projects and install MASM to the root directory of the partition. This makes it much easier to include libraries and includes such as windows.inc and friends.
MASM will proceed to run a bunch of tests to see if you’re computer is compatible and able to run MASM32. You will see a number of dialog boxes appear that require you to press the ok button.
Once the tests are complete press the extract button.
After the extraction has completed you will see another dialog box that informs you a command prompt will appear to complete the installation. Press ok and let the installation finish. It should only take a few moments.
After the installation has finished you will once again see a couple of dialog boxes that require you to press ok. You will also see a different type of dialog box similar to the one below. This runs a VB script to add an icon to your desktop for the MASM editor. If you want an icon on your desktop press yes.
Finally if everything went well you will see the final dialog box telling you the installation is complete.
Don’t run off just yet
I don’t use the default MASM editor. Instead I use Vim, or Sublime. This means I need to call the MASM compiler and linker directly from the command line to build my code. To do this you need to add the location of the MASM32 installation directory to your Path environment variable.
Adding a directory to environment variable Path on Windows 10
Open up the system properties dialog by entering the following command on the command prompt:
sysdm.cpl SystemProperties
Click the advanced tab, and click the Environment Variables button.
Next select the Path item from the list and click Edit.
On the next dialog press New and enter the path to the MASM bin directory. This contains the tools needed to compile and link assembly. For me the path is D:masm32bin. In most cases just change the drive letter if you installed to a different partition. The rest of the path is the same.
Press the ok button, and then then the apply button to save and close the system properties dialog.
Open a new command prompt and enter the following command to run the MASM assembler:
ml
If everything installed correctly and your Path is setup correctly you will see some output similar to the image below:
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All Done!
And that’s all there is to it folks. If you want to hit the ground running check out my guide on how to compile and link MASM assembly to produce an executable on Windows 10.
If you’re having any issues following this guide please leave a comment and I will help you the best I can. You can also check out the official documentation includes detailed installation instructions and FAQ’s to solve common problems.
This utility contains a set of software development tools such as the code editor, compiler, linker, debugger and browser for writing new applications.
Developer:
Microsoft Corporation
Windows version:
Windows XP, Windows Vista, Windows 7, Windows 8, Windows 8.1, Windows 10, Windows 11
MASM is a Windows tool for developing, compiling and debugging the programming code. New modules are generated using the OMF format first introduced in MS-DOS. It is important to mention that MASM is an obsolete program and no longer supported by the developer. The final version is included in Visual Studio.
Installation
You are instructed to unpack the included IMG file into the root directory of a 3,5 inch diskette. The next step is to restart the computer and adjust the BIOS settings to boot from the floppy drive. All operations are performed via the MS-DOS command line.
Assembler capabilities
With the help of this software users can utilize standard Intel syntax for compiling C applications. There is support for 16, 32 and 64-bit sources. Moreover, the assembler is compatible with hundreds of processor instructions.
It is possible to use shorthand mnemonics for segment descriptors. You can quickly generate real mode executables as well. Advanced memory management parameters are available. The resulting apps are fully compliant with the Visual C++ specification and can be modified in any popular development environment.
Features
- free to download and use;
- offers you instruments for writing, compiling and debugging C applications;
- there is support for 16, 32 and 64-bit sources;
- you can use shorthand mnemonics for segment descriptors;
- compiled apps are compatible with Visual Studio;
- compatible with all modern versions of Windows.
Microsoft AppFabric
Windows 7, Windows 8, Windows 8.1, Windows 10, Windows 11 Free
This integrated development platform lets users build, scale and manage web applications that run on IIS. There is support for the ASP.NET environment.
ver 1.1
In Class Translator
Windows XP, Windows Vista, Windows 7, Windows 8, Windows 8.1, Windows 10, Windows 11 Free
Using this program you can quickly edit class files from JAR archives. It is intended for quickly translating mobile applications to different languages.
ver 1.1
Android Studio
Windows 8, Windows 8.1, Windows 10, Windows 11 Free
With the help of this integrated development environment users can create, debug, compile and test applications for the Android mobile operating system.
ver 2022.1.1
Apache Commons Codec
Windows XP, Windows Vista, Windows 7, Windows 8, Windows 8.1, Windows 10, Windows 11 Free
This specialized utility contains instruments for decoding various data formats such as Base64 or Hexadecimal. There are phonetic encoding tools as well.
ver 1.15
AngularJS
Windows XP, Windows Vista, Windows 7, Windows 8, Windows 8.1, Windows 10, Windows 11 Free
This development tool can help users extend the basic HTML vocabulary for web applications to create responsive, expressive and readable environments.
ver 1.8
MCreator
Windows XP, Windows Vista, Windows 7, Windows 8, Windows 8.1, Windows 10 Free
Using this utility you can develop modifications for the popular Minecraft video game. It is possible to add new blocks, weapons, characters and other objects.
ver 2022.3
Universal Extractor
Windows XP, Windows Vista, Windows 7, Windows 8, Windows 10 Free
Using this simple tool, you are able to decompress files and folders. Moreover, you have the option to save the history of all performed tasks and debugging info.
ver 1.6.1
XULRunner
Windows XP, Windows Vista, Windows 7, Windows 8, Windows 10, Windows 11 Free
Using this comprehensive utility, you are able to develop and deploy Mozilla-based applications. It requires advanced programming knowledge to use efficiently.
ver 41.0.2
MASM is an assembler developed and maintained by Microsoft. MASM (8086) won’t run on Windows 7 or newer versions easily whereas it runs well on Windows XP. That is why in this post I am going to show you how to install MASM in Windows.
This tutorial is valid for Windows 10, 8.1, 8, 7.
So, Let’s begin.
Here are 5 steps to Install MASM in Windows.
1. Setup DOSBox on your OS
First, you have to download DOS Box for your PC
Visite this link (click here)
Click on Download
Wait 5-second download will start automatically
After that install DOSBox if you have any doubts about how to install DOSBox, Here is a Guide on how to install DOSBox on Windows.
2. Download 8086.rar
Visit this link (click here)
Click on Download
3. Setup 8086.rar
Open the zip file that you downloaded in step 2.
Copy the 8086 folders in drive C:
4. Create Assembly file (.asm)
Open your favorite code editor,
Enter the following code
; Hello World program by 360 Tech Explorer’s
DATAS SEGMENT
STRING DB 'Hello World!',13,10,'$'
DATAS ENDS
CODES SEGMENT
ASSUME CS:CODES,DS:DATAS
START:
MOV AX,DATAS
MOV DS,AX
LEA DX,STRING
MOV AH,9
INT 21H
MOV AH,4CH
INT 21H
CODES ENDS
END START
Save this file with the “.asm” file extension.
5. Run Assembly file (.asm) in Windows
Open DOSBox by clicking on it.
Enter the following command in DOSBox
Z:> mount c c:8086
This command will mount 8086 directory as C drive for DOSBox
Then, execute the following command to navigate into drive C
Z:> c:
If you want to write a new assembly file, execute the following command
C:> edit file_name.asm
If you already have the Assembly file, follow the following steps
Copy your Assembly file to the “C:/8086” folder (remember the name)
Then execute the following to run that file
C:> masm your_file_here.asm
C:> link your_file_here.obj
C:> your_file_here.exe