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SPAWN - An alternative to Command.com 1.0 Overview Spawn is a command processor that takes over many of the functions of command.com (to the uninitiate, this is the program that reads commands from the keyboard in PC-DOS), providing different or additional functionality. Anything that it does not provide it simply passes unchanged down to command.com. The major features of spawn are: * Command line recall and edit for the last 32 commands. * File name completion using Ctrl-D and Ctrl-F. * Ability to define symbols abbreviating command strings * Ability to define logical names to replace path names * Directories sorted in alpha order, showing the file attributes * Ability to define command strings as function keys * Enhanced delete command, with multiple file specs * Xdel command, to delete all files except specified * Selectable colors using the color command * Function to remember the last file being edited * Function to save and restore a default drive and directory * Current date and time accessible with Ctrl-T * Multiple spawn support under OS/2 Spawn is an ordinary application program. Once started it never terminates until requested to do so. It simply reads keystrokes from the keyboard, and checks to see if they translate to a command for spawn. If they do, it executes the appropriate function. If not, it invokes a copy of command.com, passing it the enigmatic command line. 1.1 Startup Spawn is started by simply running the program spawn.exe (In OS/2 protected mode, run spawnp.exe). When it loads, it will first check its own command line for a parameter of the form "/maxdir:n", where n is a number. This is the number of entries it will allocate to its directory buffer. This number represents the maximum number of files that can be processed on a call to dir, fdir, del or xdel. If this parameter is not present, n defaults to 512. Since each entry in the directory buffer requires 25 bytes, changing this parameter can significantly affect the amount of memory used by spawn. Next it attempts to open the file SPINIT.SPN, checking both the current directory, and the directory defined in the environment variable SPFILS. If found, it will read input from that file until end of file, then reconnect to the keyboard. Generally this file will contain the define and alias commands required to set up the symbols and logical names for the session. Example: set SPFILS=c:\spawn\ (note the trailing backslash) spawn (spinit.spn can be on current directory or on c:\spawn.) Spawn will perform better if command.com is loaded into a ram disk, since it makes repeated calls to command.com. 1.2 Keyboard interface Before examining the commands spawn uses, the keyboard interface is worthy of note. One of the major incentives in writing spawn was to beef up the keyboard handling of command.com. Spawn uses a fairly simple model; characters typed at the keyboard appear on the screen, as in command.com. However, where command.com uses F1-F5 to edit the command line, spawn is much simpler. The left and right arrow keys move back and forth within the command line. The delete key deletes the character under the cursor, backspace deletes to the left. The insert key toggles between insert and typeover modes (typeover is the default; the cursor changes to a block when in insert mode). Ctrl-left and Ctrl-Right will move left and right a word at a time. Home goes to the beginning of the line, End to the end. Ctrl-Home will delete all characters to the left of the cursor, Ctrl-End will delete all characters to the right of the cursor. The Escape key will delete the current line. So far nothing is really unusual, though the ability to move without deleting is handy. Also worth noting is the fact that the cursor does not need to be at the end of the command line to press <Enter>. All characters in the command line are processed regardless of the current cursor position. The up arrow and down arrow trigger command line recall. The last 32 commands are held in a queue. Pressing the up arrow will bring the previous command in the queue, pressing the down arrow will bring up the next. The queue wraps around, so you may cycle through it continuously. When a line from the queue is brought to the screen, it may be editted with the keys described above. If the line is changed, it is added to the end of the queue. If it is unchanged, it is simply reused, without being added to the queue. This can be sometimes confusing, but has the benefit that command lines tend to stay in the queue longer, and may be reused many times without causing the queue to fill with duplicates. The queue may be flushed using Ctrl-PgUp. This is handy for removing incriminating evidence of games playing. In addition to the command line recall, several other keys are available to make command line entry easier. For users accustomed to VMS, Ctrl-R will start a new line and redisplay the command line. This is rarely used but sometimes useful. In the same vein, Ctrl-X and Ctrl-U function the same as <Esc>, cancelling the current command. Ctrl-T will print the current date and time, without affecting the command line. Ctrl-D and Ctrl-F attempt filename completion, much as is done in the Unix raw shell. When Ctrl-D is pressed, the word under the cursor is treated as a path/file name. Next the directory is searched for any files starting with the fragment. (For example, if c:\tools\sc^D is entered, spawn searches for c:\tools\sc*.*). If only one file matches, the remainder of the file name is filled in for you, and the cursor advanced to the end of the completed name. If multiple files match, the name is completed as far as possible until the the possibilities diverge. (In the above example, if the files scanner.dat and scanrun.dat were present, the name would be completed until c:\tools\scan). All of the possibilities are displayed on the screen, so you may choose from the alternatives. You may then enter another character or two and press Ctrl-D to fill in the rest, or type the rest in manually. Though this sounds confusing, it is really quite simple. Ctrl-F is the same as Ctrl-D, but merely lists all the possibilities without attempting to complete the name on the command line. This is useful if you are not sure which file you want and need to jog your memory. Together Ctrl-D and Ctrl-F can greatly simplify the entry of pathnames from the keyboard. Both also understand logical names, and will translate them as required (see the section on logical names). 1.3 Operations Spawn acts just like command.com, in that you type commands at the prompt and they get executed. You do not generally care how the are executed, so long as they get done. Command.com divides commands into two different classes: internal and external. Internal commands are those for which the code resides directly in command.com and is called directly. External commands are those which are contained in another program and which must be loaded from disk. Spawn is the same way; it has a number of internal commands which are performed by spawn itself. Anything that it can not recognize as an internal command it simply passes along to command.com, which in turn decides if it is internal or external. This is required because spawn does not replicate all of the internal functions of command.com. Having said all this, it should be obvious (or at least not surprising), that the only things that are different when using spawn are spawn's own internal commands. The exception to this is the spawn keyboard interface as described above. 2.0 Commands Spawn has a large number of internal commands. Some provide no additional functionality over command.com, but are included simply because they are done so many times. DEF*INE SYMBOL TRANSLATION ---------------------------- The define command creates symbols. A symbol consists of a tag and its translation. Generally a symbol is used to abbreviate a long command line or portion thereof, or to tie a particular command to a function key. For example, consider the command define bkp backup c:\sct21\*.* a: /s/m:12-25-88 The keyword define says that we are creating a symbol. The symbol is bkp, and its translation is "backup c:\sct21\*.* a: /s/m:12-25-88". Once defined, if you type "bkp" at the keyboard, the command "backup c:\sct21\*.* a: /s/m:12-25-88" will be executed. This is the simplest form of a symbol, and serves only to reduce the number of keystrokes you must type. Consider the problem of navigating between directories. Directories are tree structured, and it is not uncommon for you to think of something as being a level higher or lower in the tree, or on the same level but a different branch. DOS provides the capabilities for navigating the tree, which are seldom exploited. Few realize that the command "cd .." will change to the parent directory (same branch, one level up) or that "cd ..\sibling" will go up and over. The command "cd child" will go one level down in the tree. These commands are seldom used partly because of the awkardness of typing "..\". Consider the following symbols: define side cd ..\ define up cd .. define down cd Typing "side sibling" translates to "cd ..\sibling" (it is important that there be no trailing spaces after the ..\ when the define is done, since we wish the sibling to bind directly to the ..\, and not as "..\ sibling"). Similarly "up" translates to "cd ..". These shorthands are very convenient for traversing large directory trees. The astute reader may have noticed that the heading of this section said "DEF*INE". The asterisk is part of the symbol definition. Its presence indicates the minimum acceptable abbreviation for the symbol. "def*ine" says that "def", "defi", "defin", and "define" are all valid, but "de", "defo" and "defile" are not. An asterisk can be placed in any symbol to define the minimal abbreviation. Function keys can be defined as symbols. Any symbol with the form "define funct_keyN", where N is the number of a function key, defines that function key as a symbol. Function keys will take precedence over whatever command line is displayed; that is, if a function key is pressed while a command line is being built, only the function key press is processed. Function keys are always acted on immediately, so they can not be used to enter partial commands. You can think of pressing a function key as the equivalent of <Esc>, function key, <Enter>. Only F1 - F10 may be defined, using the syntax funct_key1, funct_key2, etc. Once created, symbols can not be deleted, though they can be changed by defining the same symbol with a different translation. The definition of all symbols can be list by using the "show sym" command. ALIAS LOG_NAME PHYS_NAME ------------------------ The alias command defines a logical name. Logical names are similar to symbols but different in scope and grouping. To be translated, a symbol must always be the first token (basically a word) on the command line. Symbol translation is single level, and is assisted with the abbreviation logic. Logical names are intended to serve as shorthand for file or path names, but can be treated similarly to symbols. When encountered anywhere on the command line, the logical name is translated to its physical name. For example, consider the following: alias bootdir c:\system\boot dir bootdir The alias command defines the logical name bootdir to mean the directory c:\system\boot. The dir command will list all of the files in the directory c:\system\boot. So far this is very similar to symbol translation. However, a logical name can be combined with a physical name using a colon (:). alias bootdir c:\system\boot dir bootdir:vdisk.sys The dir command in this instance translates to dir c:\system\boot\vdisk.sys. When a logical name is translated, the translation routine decides whether the colon should be left in place, omitted, or translated to a '\'. It always attempts to turn the physical name into a file name if possible. Logical name translation is recursive; consider alias bootdir c:\system\boot alias ramdriver bootdir:vdisk.sys To resolve ramdriver, the logical name bootdir must be translated, so the definition of ramdriver becomes "c:\system\boot\vdisk.sys". More than one logical name can appear on a line. Consider alias rev20 c:\sct20\source alias rev21 d:\sct21\source copy rev20:*.c rev21:*.old In this instance both logicals are translated, so the resulting command is "copy c:sct20\source\*.c d:\sct21\source\*.old". Once assigned, logical names remain in effect until destroyed with the DEASS command. Logical names are translated by Ctrl-D and Ctrl-F, but are not completed by them. The definition of all current logical names can be listed with the "show log" command. DEASS*IGN LOG_NAME ------------------ This command is the opposite of alias. It removes from the logical name table the logical name specified. VE*DIT EDITOR_PARAMS --------------------- The ved command is designed to work with a text editor (in my case, not suprisingly, vedit), but can really be applied to any program. What it does, is examine the command line associated with the command; if it is not null, it saves it. If it is null, it appends the last value of the command line to the translation of the symbol and executes that. Though the description is rather long winded, the explanation is simple enough; if you do not supply a filename to a text editor, it will start up with the last one you worked on. When a file name is saved, it is expanded into a complete filespec, including drive and directory. In this way, the default directory may be changed, but the editor will still edit the same file. The actual program executed by the vedit command is the value of the environment variable VEDEXE. For example: set VEDEXE=c:\jfe\vedit.com spawn vedit config.sys Editing file: c:\config.sys (do your editing here...) vedit Editing file: c:\config.sys (do your editing here...) The vedit command has some smarts; if there is more than one token on the command line it will not attempt to expand out file specs, and if the file spec contains a \ or : it assumes it is already a pathname and will not try to expand it. Under OS/2 more applications are smart enough to remember what they were doing before exiting, and this command is not needed nearly as often. What I have done in OS/2 is to reassign this command so that it invokes make with the last makefile used. The proper commands are (these should go in spinit.spn): define ve*dit mep ; this switches the normal vedit to mep define make $$i ; define make to internal command i define funct_key5 ved ; keep f5 as editor invocation define funct_key6 $$i ; but make f6 remember the command line Then in you config.sys for OS/2, place the following: SET VEDEXE=<your make path>make.exe DIR*ECTORY and FDIR*ECTORY -------------------------- One of the more obnoxious commands in PC-DOS is the dir command. Its chief offenses are that it does not sort the files before displaying them, it does not give the total size of the files listed, it does not display the attributes of the files, and it will only accept a single specification at a time. The spawn dir command fixes all of these problems. Syntactically, the format of the command is: [f]dir[ectory] [file_spec [file_spec [file_spec... ]]] [/p][/w] That is, the word dir or fdir, followed by zero or more path/file specifcations. The actual rules for interpreting the file specifications are surprisingly complex, but quite intuitive if you are used to the DOS version of the command. If the /p qualifier is present, the display will stop every screenful and prompt for a key before continuing. This qualifier may appear anywhere on the command line. In DOS spawn always assumes that a screen is 25 lines. In OS/2 it is smarter and will use the proper number of lines when /p is used. (If you are running in a window, the number of screen lines is the number of lines the window would have when maximized, not the number of lines displayable at the current size of the window. The scroll bars on the window can move around within the full screen size). The /w qualifier displays only the file names, and displays as many as possible on each line. Directories are preceded with an asterisk (*). The output from spawn is sorted alphabetically by name (to make directory management easier, subdirectories always appear at the beginning of the display), with the file attributes shown at the beginning of the line. The three possible attributes are 'r' for read only, 'h' for a hidden file, and 's' for a system file. Absence of an attribute is indicated by a dash (-), so normal files will be preceded by a "---" on the directory listing. The dir command will not display hidden or system files, while the fdir command will. Otherwise the two commands are identical. Entry of multiple file specifications to the dir command complicates matters. For example, the command: dir *.c *.lst will show all of the .c and .lst files on the current directory, sorted by alphabetical order. So far, so good. The command: dir c:\*.sys c:\system\boot\*.sys will show all of the .sys files in both directories -- however, because multiple directories are involved, the directory name will be shown preceding each file, and the sorting will sort by the full pathname, grouping all of the files in each directory together. In contrast, the command: dir sl:*.c sl:*.obj (where sl is a logical name) will translate the the logical name sl, then give a directory of all the .c and .obj files on the directory that sl evaluates to. In this case, since all of the files reside on the same directory, only the file names are displayed. Finally a command like: dir *.c .\*.c *.c will produce a list of all the .c files on the current directory, and a list of the same files preceded by ".\". This is because so far as spawn is concerned, two different directories are involved: the current (no string) and the directory ".\" (which evaluates out to mean the current directory). The duplicate *.c specs do not bother it -- the duplicates created there will be flushed and only displayed once -- but it will be fooled by the ".\". The moral of the story here is that if you don't try to fool spawn it won't try to fool you. DEL*ETE and XDEL*ETE -------------------- Spawn replaces the del command from PC-DOS with its own version (by default ERASE is not defined, and will invoke the DOS erase command), which has much of the same enhancements that the dir command does. It accepts multiple specifications on the same command, and has a /v option that prints out the name of each file as it is deleted. Syntactically, the command is: [x]del[ete] file_spec [ file_spec... ] [/v] Up to ten different file specifications can be included on the command line. Unlike DOS, the spawn delete command does not prompt with "Are you sure?" if the file specification evaluates out to *.*. If you ask for *.*, you get *.* with no backtalk. The xdel command is similar to del, but deletes all of the files except those listed. For instance, xdel *.c makefile.* will delete all the files on the current directory except those with a .c extension or a name portion of makefile. Overlapping specifications (in this instance a file makefile.c) cause no problems. Xdel attempts to establish a target directory for its deletions. It need not be the current directory, but all file specifications must evaluate out to the same directory. For instance, the command xdel c:\*.sys c:\system\boot\*.sys will give an error message to the effect that only one target directory can be referenced, while the command xdel c:\system\boot\*.sys c:\system\boot\*.drv would work without complaint, deleting all files on c:\system\boot that do not end .sys or .drv. Xdel also supports the /v option (which may be anywhere on the command line), to print out the name of each file that is being deleted or preserved. Xdel is vulnerable to confusion in the same way that the dir command is, by pathnames that are different but actually refer to the same path; in this instance it will give the error about multiple target directories. SDIR and RDIR ------------- The sdir command simply saves the current default drive and directory for later use. It produces no output. This command is automatically executed when spawn is started. The rdir command will set the default drive and directory to the values saved by sdir. Again, no output is produced. You may find it handy to tie these commands to function keys, so that they can be quickly invoked: def funct_key7 sdir def funct_key8 rdir COLOR ----- The color command sets the color that spawn will use for its output and the output of programs that it calls, unless those programs override it with their own color setting (as most do). The syntax is: color [bright] foreground_color on background_color where foreground_color and background_color must be one of: black, blue, green, cyan, red, magenta, yellow or white. The bright parameter is optional and will cause the foreground color to be high intensity. Good choices for color are white on blue and green on black, but by all means experiment. Color setting is done primarily through ansi.sys, so the ansi.sys device driver must be installed in your config.sys file. Failure to install ansi.sys will not cause catastrophic errors, but output will look somewhat odd. The default color setting is green on black. PTOG ---- The ptog command stands for "prompt toggle". Unlike PC-DOS (and one of the few areas where spawn is not as versatile as command.com), the prompt in spawn is not defineable. By default the prompt is the volume name of the default drive (or drive letter if the default drive is unlabelled), followed by the default directory and a greater than sign. If this is undesirable, or too long, the ptog command will minimize the prompt. Typing ptog again will change it back. In real mode (DOS or OS/2 compatibility mode) the prompt is preceded by an (R) to indicate real mode. In OS/2 protected mode the prompt is proceeded by the session nickname, such as (Bert). When minimized, the real mode prompt is R$, and the OS/2 prompt is n$, where n is the ordinal number of the session. (Ordinal numbers are generally assigned in the order of startup, until one session terminates, in which case the next startup will reuse its ordinal number. See the section on OS/2 for more on this stuff). HIST ---- This command simply lists the commands in the keyboard history queue. The last 32 commands are saved, not counting function key presses or commands that were reused from the queue. SHOW { MEM*ORY LOG*ICAL SYM*BOLS VED*IT VER*SION } -------------------------------------------------- The show command requires one of the arguments shown above. Each produces different output. SHOW MEM will display the amount of memory installed (up to 640KB), the amount used by the system (DOS, device drivers, TSR's, etc.), the amount used by spawn, and the amount available for programs called by spawn. This last value will generally be about 4K more than the value shown by the chkdsk command, because of the overhead incurred by calling command.com to call chkdsk. In OS/2 protected mode the show mem command is not nearly as interesting. It shows the approximate size of the spawn program itself (not counting environment and shared memory), and the size of the largest remaining free block. This is the amount that is available for other applications to use. This may not represent the true amount of memory remaining in the system, since OS/2 may well be able to coalesce free blocks if a request is made for a block exceeding the remaining size. The virtual memory aspects of OS/2 and the MEMMAN command in the config.sys file give it considerable flexibility to find memory. SHO LOG will display the logical and physical names of all the defined logicals. SHO SYM will display the symbol and translation for all of the symbols defined. SHO VED will display the program tied to the vedit command and the currently saved command line for that program. SHO VER will display the version level of spawn. KILL ---- This command exits spawn, returning you to command.com (or whatever program invoked spawn). CLS and CD and SET ------------------ These commands do nothing that command.com doesn't do, but are implemented in spawn so that a copy of command.com doesn't have to be loaded just to do these trivial functions. Additionally, SET is internal because copies of the environment are always passed by value, so it is not generally possible for one program to modify anothers environment. Spawn will inherit the DOS environment, but after that maintains its own. Changing drives is also done internally (a command such as "d:"), because in OS/2 the notion of default drive and directory are local to a process and no other process can change spawn's default drive and dir. @ COMMAND QUALIFIER ------------------- Technically speaking, @ is a command qualifier and not a command, but it helps to think of it as a command in and of itself. The presence of an @ sign preceding a command indicates that the next token on the command line is a filename containing commands for spawn to execute (analogous to a DOS batch file). The file is presumed to have an extension of .SPN, and to be either on the current directory or in the directory referenced by the SPFILS environment variable. Any spawn or DOS command can be executed inside of a spawn file, though the DOS commands that work only within batch files are not available. Spawn will not echo the contents of .spn files. When all commands in the file have been read, input is reattached to the keyboard. & COMMAND QUALIFIER ------------------- The & is also a command qualifier. It tells spawn that instead of invoking command.com to execute the command line, the first token should be treated as a program name and executed directly, without going through command.com. This is slightly faster, and saves about 4KB of memory, but will not work for commands internal to command.com, and commands which are not well behaved about reading their command line. This command will search the current PATH for the file to be executed. This qualifier is also available in OS/2, but to avoid conflicting with the normal usage of the & in OS/2, it has been changed to the right bracket character "]". OS/2 PROTECTED MODE ------------------- The program spawnp.exe is an OS/2 protected mode version of spawn. In general the two behave identically, with the slight differences noted in the descriptions above. However, the OS/2 version has a different prompt scheme (as described in the PTOG command), and has two commands that are not available in DOS mode. HIGHT nickname (OS/2 only) --------------------------- This command changes the session nickname. The session nickname is the word displayed in parentheses before the volume label as part of the prompt. If the nickname is blank the current name is printed. Nicknames can consist of any ASCII characters up to a length of 31. This command is not available in DOS (real) mode. SYNC {/query | /notify | /nonotify} [nickname] (OS/2 only) ---------------------------------------------------------- The sync command is used to (what else) synchronize processing between multiple OS/2 sessions. It's intended usage is to give you a quick method of checking on another process. For instance, suppose you are using 3 screen groups: an edit process, a compile process, and a test environment. You edit a file, flip over to the compiler process to compile, go back to the editor and edit some more, then want to know if the compile has finished so you can test. You Alt-Tab through all screen groups until you find the right process, discover it is not done, then Alt-Tab back. All in all, a laborious process. With spawn, you use: sync /query Bert spawn responds with Bert is busy doing "make" or Bert is idle. Bert in this instance is a session nickname. Sync /query is a single check on the status of a session, or, if no nickname is given, all sessions. sync /notify is slightly more sophisticated. If notify is turned on (it is enabled for all sessions by default), whenever another session completes a command while in the background, the foreground session will display a message of the form session has finished "command" where "session" is the session nickname and "command" is the command that was just executed. /notify is only operative while spawn is in the foreground and is taking input from the keyboard. sync /nonotify disables notify mode for either a single session or for all sessions if no name is given. This command is not available in DOS (real) mode. QUICK REFERENCE --------------- Getting started: Spawn uses two environment variables: VEDEXE should be set to the full pathname of the program to be used with the vedit command. SPFILS should be set to the directory where .spn (spawn batch files) can be found. This specification must include a trailing backslash (i.e. c:\spawn\) The file spinit.spn (in the SPFILS directory) is executed upon startup. In DOS, start spawn with: spawn /maxdir:n (a good value for n is 250) in OS/2, start spawn with spawnp /maxdir:n (again, n=250 is about right). KEYBOARD ENHANCERS: Ctrl-D Complete filename Ctrl-F List matching filenames Ctrl-T Display date and time Ctrl-R Repaint current command line Esc Delete current command line Ins Toggle between Insert and typeover modes Up arr Restore previous command line from queue Dn arr Restore next command line from queue Lft arr Move cursor left Rgt arr Move cursor right Home Move cursor to beginning of line End Move curosr to end of line Ctrl-Rft Delete all characters to left of cursor Ctrl-Rgt Delete all characters to right of cursor Ctrl-PgUp Delete queue of previous commands COMMANDS: DEF*INE SYMBOL TRANSLATION Define a symbol ALIAS LOG_NAME PHYS_NAME Define a logical name DEASS*IGN LOG_NAME Destroy a logical name VE*DIT [EDITOR_PARAMS] Invoke a text editor, restoring last command line if none given [F]DIR[ECTORY] [FILE_SPEC [FILE_SPEC...]] [/P][/W] Display a directory for normal files (dir) or all files (fdir). Pause every screenful if /p is given. Display in wide format if /w is given. [X]DEL[ETE] FILE_SPEC [ FILE_SPEC... ] [ /V ] Delete files (del) or delete all but specified files (xdel). Be verbose if /v is given. SDIR Save current drive and directory. RDIR Set default drive and directory to those saved by SDIR. COLOR [BRIGHT] FOREGROUND_COLOR ON BACKGROUND_COLOR Set colors to use for display. PTOG Toggle prompt between default and minimized. HIST Show contents of history buffer. SHOW { MEM*ORY LOG*ICAL SYM*BOLS VED*IT VER*SION } Show things. KILL Terminate spawn @ COMMAND QUALIFIER Invoke a spawn batch file. & COMMAND QUALIFIER Call a program directly (no command.com or cmd.exe) HIGHT nickname (OS/2 only) Set the session nickname. SYNC {/query | /notify | /nonotify} [nickname] (OS/2 only) Query the status of another spawn session, or enable and disable sync notifications. TECHNICAL NOTES --------------- Spawn is written entirely in MicroSoft C, version 5.1. Its roots go back to 1984, when version 1 was written in Aztec C. Spawn has grown over the years, and now bears little resemblence to the original. Portions of the original code still survive as a testament to how ugly the code that is written by a beginning C programmer can be. As of version 2.0, spawn is spread across 4 source files. spawn.c contains the bulk of the code, and is primarily concerned with actually implementing the commands. Input.c contains the keyboard routines and various support functions. Both of these source files are compatible with both OS/2 and DOS. The other two source files are sysdep-p.c and sysdep-r.c, and are the system dependent functions for protected and real mode. These files have the same entry points, but the implementation of the functions is different. The DOS version links with sysdep-r and the OS/2 version links with sysdep-p. I have never claimed that spawn is the best product in its class, or that its quality is all it could be. Much of the code could be smaller and cleaner, and the source documentation in particular ranges from nonexistent to out of date. All of that said, it works and I know what does what, so it meets my purposes. If there is a function you would like to see added, you can take a crack at it yourself, or let me know and I may try it. As of the moment I have no major features planned -- I am most likely to spend the effort to try and get the amount of memory consumed in real mode down. Happy computing.