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ZIP.DOC ------- Instructions for ZIP.COM Fast File Transfer Utility version 2.02 (03 Nov 1995) (c)1988-95 E. Meyer Requires: Two PC compatible computers with DOS 2.x or above; Null modem cable. ================================== CONTENTS ================================= 1. INTRODUCTION: Brief description; Copyright and Licensing 2. PREPARING TO USE ZIP A. Operating modes B. Setting serial port and speed C. File attributes and directory creation D. Screen output modes E. Clock synchronization 3. TRANSFERRING FILES A. Sending files B. Receiving files C. Selecting files from a group D. Reconciling and overwriting files E. Backing up all subdirectories F. Directory, Delete, and Log commands G. Waiting for a connection 4. SERVER MODE A. Sending and fetching files B. Server Directory, Delete, and Log commands C. Comparing directory contents D. Server Time command 5. FURTHER USAGE NOTES A. Summary of options B. Examples of command-line syntax C. Automating use of ZIP (Redirection, @files, Batch files) 6. UTILITY PROGRAMS A. Copying ZIP itself with ZIPDUP B. Changing defaults with ZIPSET 7. TECHNICAL INFORMATION A. General information B. About serial cables C. Using ZIP on HP95/100/200LX palmtops D. Error messages E. About the program and author ============================== 1. INTRODUCTION ============================== Anyone working with two computers probably needs to transfer files between them regularly. But especially when large amounts of data are involved, exchanging floppy disks quickly grows tedious; and not all computers have the same disk sizes, or disk drives at all. Keeping track of new or modified files on each computer gets to be a problem, too. ZIP is a tiny, fast utility to transfer files between two PC compatible computers, using a common "null modem" serial cable. It can be used from the DOS command line or a batch file, or run from an interactive menu. It transfers files as simply as using the COPY command, and has options that make it easy to back up or reconcile directories on both computers. Ideal for laptop or palmtop computers, even long outdated PC's, it requires very little disk space and memory. There are good retail programs for this purpose, if you want to pay well over $100, and they even come with a cable. But if you have or can find your own cable, ZIP offers a much cheaper alternative. ZIP doesn't include as many features as these more elaborate programs; but it also doesn't take time to load or install, and doesn't consume precious system memory when not actually in use. In fact, even if you already have another more complex program, you may still find ZIP easier to use in many situations because of its small size and simplicity. ZIP transfers files many times faster than the binary upload/download protocols (like XMODEM) of ordinary telecommunications software. ZIP 2.0 can even work over twice as fast as many similar utilities that also claim to operate "at 115200 bps", the maximum speed of the PC serial port, because it uses additional techniques where feasible to further improve the transfer rate. ZIP's actual throughput also depends on your computer speed, typically running about 8 to 10 kilobytes/second on 8086 PC's, or 16 to 24 k/sec on 80486's; results will vary according to your system configuration and the size, type, and location of files involved. ZIP is designed to operate at very high transmission speeds with a direct cable connection, but it can also be used at slower speeds in applications that demand this. Use with a modem over a phone connection established by telecommunications software is conceivable, but not recommended or supported. (Note: ZIP is a PC serial communications program, and has no connection with the more recent file archive utility "PKzip", formerly "PKARC", by Phil Katz.) HOW YOU GOT YOUR COPY OF ZIP ZIP circulates widely as "shareware", giving you the opportunity to try the program at no cost, and to share it with others -- hence the name. If it doesn't meet your needs, you don't have to pay for it. If you find the program valuable and continue to use it, you can "register" your copy for a modest fee. In return, you get an update disk and support from the author. Shareware offers some unique advantages over retail software, because users interact directly with the author. Obviously, costs are kept down because glossy packaging, advertising, and retail markups are eliminated. But shareware can also resist market trends and continue to provide useful kinds of products that the big corporations have abandoned. And shareware authors can respond more directly to user requests and concerns than software publishers who release an update only when it seems profitable. Shareware works when users give program authors useful feedback, and most of all, when users support authors by registering their programs. This makes it possible for quality shareware to continue to develop and improve. Please support shareware by registering any programs that you use. The use and distribution of ZIP are governed by the "COPYRIGHT AND LICENSE" information below. Please read this carefully! FILES YOU SHOULD HAVE Be sure you have all the files which should be included in this package: ZIP.DOC - This documentation file. ZIPxx.UPD - Update notes and version history. ZIP.COM - The file transfer program. ZIPSET.COM - The default option setting utility. ZIPDUP.COM - The initial duplication utility. ZIP.ICN - An icon for the HP100/200LX Application Manager. ORDER.FRM - Registration/site license order form. FILE_ID.DIZ - Standardized description for BBS operators. COPYRIGHT AND LICENSE INFORMATION The ZIP program and documentation are copyright (c)1988-95 Eric Meyer, all rights reserved worldwide. They may not be circulated in any incomplete or modified form, nor sold for profit, without written permission of the author. The use or sale of ZIP is subject to the following terms: PERSONAL USE. If you find ZIP valuable and continue to use it, you are encouraged (but not required) to register, and help support the development of high-quality, affordable software: INDIVIDUAL REGISTRATION ..... $30 (US) Registered users receive several benefits: * The latest version of ZIP (and other useful programs) on disk direct from the author. * Technical support if you encounter problems using ZIP. Future upgrades can be ordered on disk when desired. * A registration certificate verifying the legality of your personal use of ZIP at your workplace as well. SITE LICENSES. Any company or institution wishing to use ZIP in the course of its business MUST purchase a SITE LICENSE. The cost of the license is modest, and varies according to the number of computers on which ZIP may be in use in the workplace: Up to 10 copies................. $50 (US) Up to 20 copies................ $100 Additional copies over 20........ $2 each The purchaser of a site license receives several benefits: * The latest version of ZIP (and other useful programs) on disk direct from the author. * Technical support if you encounter problems using ZIP. Future upgrades can be ordered on disk when desired. * A license certificate documenting the legality of your company's use of ZIP. * Your employees can also use ZIP at home and share it with others without raising issues of software piracy. COMMERCIAL SALE. Any software dealer or library may offer ZIP for sale, as long as the price charged for the disk containing ZIP does not exceed US $6 (for CDROM, $30). With this single exception, the sale of ZIP, either alone or together with other software or hardware, requires a licensing agreement. Please write for terms. ORDERING AND SOURCES. Site licenses and individual registrations may be ordered directly from the author (see address below), by check or money order in US currency; purchase orders are also accepted. CREDIT CARD ORDERS (VISA,MC,AmEx,Discover), including international, for licenses and registrations must be made through the Public Software Library, P.O. Box 35705, Houston TX 77235. TO PLACE AN ORDER ONLY, phone toll-free (800)242-4775; for related inquiries, phone PSL at (713)524- 6394, fax (713)524-6398, or email PSL at CompuServe [71355,470], Internet 71355.470@compuserve.com. Mention item #10304. (There is a $5 surcharge for credit card orders.) ZIP is distributed widely through "shareware" channels. Users with a modem can download the latest version as the archive file ZIP(xxx).ZIP, available from either of the two primary distribution points: (1) Glendale Litera BBS - Glendale, CA (818)956-6164. (2) On CompuServe, ZIP.ZIP in library 4 (DL4) of the PCCOM forum. In addition, ZIP circulates on a variety of other remote systems, and is available by mail from many good software libraries, including the Public Software Library (order disk #1674). FOREIGN USERS. In many countries, retail software is scarce or expensive, and shareware is an even more attractive alternative. Registrations from overseas are warmly encouraged, and users receive full support, including disks by airmail, at no extra charge. Payment can be made by inter- national credit card through Public Software Library; or you can send money orders in US currency, drawn on a US affiliate bank, directly to the author. Modest amounts of US cash ($50 or less) can also be sent safely by registered mail. Address all correspondence to the author: Eric Meyer 3541 Smuggler Way CompuServe: [74415,1305] Boulder, Colorado 80303 USA Internet: 74415.1305@compuserve.com THE CUSTOMARY DISCLAIMER: You undertake to use ZIP at your own risk. The author does not warrant the suitability of ZIP for any particular purpose, and assumes no liability for damages of any kind resulting from its use. ========================== 2. PREPARING TO USE ZIP ========================== In order to use ZIP, you need to have a copy of the same version of ZIP.COM on both computers, and a "null modem" cable (or equivalent) connected between their serial ports. If incompatible disk drives prevent you from getting ZIP.COM itself onto the second computer to begin with, you can use the ZIPDUP utility (see COPYING ZIP ITSELF). For further explanation of serial cables, or using ZIP on a Hewlett-Packard palmtop computer, see TECHNICAL INFORMATION. To achieve the fastest transfers, you should send files to/from hard disks or RAMdisks, rather than slow floppy disk drives. Also, certain kinds of memory-resident software, especially disk compression utilities like Dbl/DrvSpace or Stacker, can significantly reduce ZIP's effective speed, particularly on slower computers like palmtops. If a connection cannot be established due to your cable wiring or serial port and speed selections, the message "Ready" or "Waiting" will remain on screen when you try to run ZIP; correct the problem and try again. While you are first learning to use ZIP, it will be easiest to put one computer in server mode ("ZIP /V") and operate the other in menu mode ("ZIP"), so you can explore the various menu selections and be prompted for all necessary input. During file transfer, ZIP will show the name and size of each file in succession, with a running total of the amount sent so far. ZIP can be interrupted by pressing Escape, ^C, or Ctrl-Break: (1) during the initial connection attempt; (2) at any user prompt; (3) during file transfer (on the receiving end, your keystroke will not be noticed until the current file is finished). CAUTION: ZIP is capable of overwriting or deleting existing files! Be careful not to inadvertently destroy important files (such as those in the root directory of your hard disk) while learning to use this program. ----------------------------- A. OPERATING MODES ---------------------------- ZIP is a versatile program, and can be operated in a number of different ways. First, you have a choice between two user interfaces: MENU-DRIVEN OPERATION. Simply type "ZIP" on both machines. You will see a menu of choices including sending, receiving, or fetching files; listing or comparing directories; logging a new directory; deleting files; entering server mode; unlinking the server; setting the time; changing parameters; or getting help with options. Just type the highlighted letter of your selection. COMMAND-LINE OPERATION. Any single operation can be performed from the DOS command line, by providing the correct arguments and options. For a brief help message explaining syntax and options, type "ZIP /?". Note that certain command-line options (/M, /A, /X, /1-4, /B) can also be used when invoking ZIP in menu mode (for example, "ZIP /M"). ZIP also offers two different operating modes for exchanging files, allowing you to choose whichever is most convenient at the time: SYMMETRICAL MODE. ZIP runs the same way on both computers; complementary "Send" and "Receive" commands are executed on each end as required. This is the first method described in the section TRANSFERRING FILES below. CLIENT/SERVER MODE. One computer is put into "server mode", waiting to act as a server or slave to the other computer, the "client", on which all commands are executed. This method, which also allows further operations like directory comparisons, is described under SERVER MODE. Menu operation and client/server mode are usually most convenient when you plan to perform a series of tasks from the keyboard; command-line use provides a quick way to perform a single task, and works well in batch files. -------------------- B. SETTING THE SERIAL PORT AND SPEED ------------------- These are not factors that will complicate your everyday use of ZIP; they are simply options for you to be aware of. The serial port selection only needs to be set once (if at all) on each computer with ZIPSET, and most users will never need to change the transmission speed (baud rate). PC-compatible computers typically have one or two serial (RS232C) ports, sometimes as many as four, called COM1 through COM4, and on each computer you must tell ZIP which port you will be connecting its cable to. If in doubt as to which designation corresponds to each physical socket on your computer, consult your manual; see also the description of ports and cables under TECHNICAL INFORMATION, below. By default ZIP uses the COM1 port, but you can select another standard COM port instead: in menu mode, just choose "P"arameters, then select a port (1-4). On the command line, specify the following option: /1-4 = use port COM1-4. Normally, of course, you would go to this trouble only initially, or in unusual circumstances; if you are going to be using ZIP regularly on a port other than COM1, you can simply use ZIPSET to change the default, and then forget about port numbers. Serial data transmission can take place at a wide range of speeds. ZIP normally works at the fastest possible rate, 115200 bps; use of slower speeds is not recommended, unless you find it to be necessary to accommodate certain computers or software environments. In any event, the same speed must be set on both ends. In menu mode, just choose "P"arameters, then select a speed (by letter, from the menu). On the command line, specify the option: /Bnnnn = use speed nnnn (BPS) The allowed speeds "nnnn" are 115200, 57600, 38400, 19200, 9600, 4800, 2400; each may be abbreviated to as few as two digits ("/B96"). The default speed can also be changed with ZIPSET, if desired. You will see a note in the ZIP signon message, "Speed=____ Port=____", giving the port address and speed currently in use. ---------------------- C. FILE AND DIRECTORY HANDLING ----------------------- ZIP allows you to specify how you want it to handle certain DOS file attributes. (If you don't know what any of this means, you can either turn to your DOS manual or decide not to worry about it.) By default, ZIP does not list or transfer Hidden or System files; it preserves all DOS attributes, including Archive, as they were on each source file; and an error is generated if you attempt to overwrite or delete an existing Read/only file. You can also choose whether you want ZIP to create a new directory when the one you specified to receive files or log in does not already exist; by default, ZIP simply reports an error in such cases. To examine or alter these settings, in menu mode, just choose "P"aram- eters; then press "N" to change new directory creation, or "T" to change file attribute handling. There are four attribute settings: include Hidden files? preserve Archive attribute? include System files? overwrite Read/only files? Press a letter "H,S,A,R" to change any setting from YES to NO. They may be specified independently on either end; the settings on the client or sending end govern each operation. On the command line, you can specify the option: /A = ADD (create) new directories (Note: if you have used ZIPSET to make directory creation your default, the /A option will reverse this.) There is no command-line option to change the file attribute settings, but the defaults can be changed with ZIPSET. --------------------------- D. SCREEN OUTPUT MODES -------------------------- ZIP is capable of displaying in several colors or shades on computers with color or greyscale capability (colors are chosen with ZIPSET). However, you can instead select simple DOS (monochrome) output mode if you prefer. This may be desirable on displays that are hard to read or cannot display different colors or video attributes effectively; it is also necessary if you wish to redirect screen output (see AUTOMATING). On the command line, specify the option: /M = use MONOCHROME output You can also make this your default with ZIPSET. (Note: if you have done so, the /M option will reverse that choice, producing color output.) -------------------------- E. CLOCK SYNCHRONIZATION ------------------------- It is advisable to ensure that the system clocks on your computers agree closely with each other; once they differ significantly, the timestamps on files may not correctly indicate which computer has the later revisions. Therefore, when ZIP is about to perform an operation which involves file timestamps, it first compares the two system clocks. If ZIP is performing a directory Comparison (/C) and finds that the clocks differ by more than the "clock synch tolerance", a warning is given. (The synch tolerance is 5 minutes by default, but can be changed or disabled with ZIPSET.) If ZIP is attempting a file transfer by timestamp (/T) and finds that the clocks differ by more than the tolerance, the transfer is aborted. To correct the situation, you could use the DOS commands TIME (and/or DATE) on each computer; better yet, you can synchronize the clocks automat- ically using ZIP itself. (See SERVER TIME COMMAND.) =========================== 3. TRANSFERRING FILES =========================== A SIMPLE EXAMPLE: Suppose you have a file REPORTS in directory C:\WORK on your laptop computer, and you'd like to send it to directory D:\JONES on your desktop PC. The cable is connected between the laptop's COM1 port and the desktop's COM2. Here is a single command to do it: Laptop: ZIP C:\WORK\REPORTS /[D:\JONES] /1 Desktop: ZIP /R /2 Alternatively, you could perform the transfer in menu mode, with prompts to guide you through each step: Laptop: ZIP /1 Desktop: ZIP /2 "S"end "R"eceive Files: C:\WORK\REPORTS To: D:\JONES "Q"uit "Q"uit Note that if either C:\WORK or D:\JONES was the current directory on the computer in question, it would not have had to be specified. Also, the "/1" probably wasn't necessary on the laptop because COM1 is the normal default; similarly, if you're going to be using COM2 on the desktop all the time, you would want to use ZIPSET to set the desktop copy of ZIP to use COM2 as the default, in order not to have to specify "/2" every time. So the transfer will often be as simple as: Laptop: ZIP REPORTS Desktop: ZIP /R If you can get such a transfer to work, you can go on to explore the details which follow. (If not, recheck your cable, port settings, etc.) ------------------------------ A. SENDING FILES ----------------------------- Transferring files between computers with ZIP is as easy as copying them from one disk to another. In menu mode, simply select "S"end, and you will be prompted for the filename(s) and then a directory to send them to. (For the default directory on the other end, just press ENTER.) On the command line, give the filename(s) to send as part of the ZIP command, and if you want to specify a destination directory, you can add it as an option in brackets: C> zip FILESPEC /[DESTDIR] In either mode, the "FILESPEC" can be a single FILE (including path), or a GROUP specified by wildcards (eg, *.BAK), or an "@FILE" (see AUTOMATING), or a LIST of any of these delimited by commas or spaces. Each item assumes or continues the same path as the previous one, unless the new one begins with a drive or root directory. Thus the list: d:\sf\gort, ltrs\*.892, klaatu refers to files D:\SF\GORT, D:\SF\LTRS\*.892, and D:\SF\LTRS\KLAATU. Any other desired options may also follow the filename(s), though only certain ones (/S and /N,E,T,P) are valid in menu mode. Take care not to send two files with the same name to the same receiving directory, as one would overwrite the other. Whether or not ZIP sends DOS Hidden or System files can be determined with ZIPSET. The size of each file to be sent is shown in "k" (1k = 1024 bytes), and the transfer in progress is indicated by continuously updating the amount sent. This progress indication disappears when the transfer is complete. ----------------------------- B. RECEIVING FILES ---------------------------- In menu mode, simply select "R"eceive, and you will be prompted for the directory to receive files into. On the command line, specify the option: /R = RECEIVE files and, if you want, a directory to receive files into, in brackets: C> zip /r[DESTDIR] Do not supply a filespec before the /R option; the sender determines the files to be sent. By default, files are received into the current directory. Any destination directory specified by the sender overrides the receiver's directory. If the specified directory does not exist, the /A option determines whether ZIP attempts to create it. Of the file selection options, only /P may be used when receiving. A received file bears the same filename, DOS timestamp, and file attributes as the file sent (except that whether the Archive attribute is preserved is user-configurable). ---------------------- C. SELECTING FILES FROM A GROUP ---------------------- If you want to transfer only certain files from a group (like *.DOC) with ZIP, you can request that you be prompted to confirm each file individually: you will be asked to press a key (Y/N) to determine whether each file is to be sent. After the file (or for receiving, directory) names, in either menu or command-line mode, specify the option: /P = PROMPT to confirm files individually If option /P is in use on the receiving end and "No" is entered, the message "<Declined>" will appear on the sending end. This option can be specified independently on either or both ends, but has no effect in server mode. (In menu mode, you can select "O"ptions for a help message describing the file selection options, including /P.) -------------------- D. RECONCILING AND OVERWRITING FILES ------------------- ZIP offers several features that are particulary useful for reconciling the contents of directories which are duplicated (in whole or part) on both computers. By default, ZIP doesn't care what files may already exist on the receiving end: it will transfer all files specified, whether or not they overwrite existing ones. Three options are provided to modify this behavior. After the names of files to be transferred, in menu or command-line mode, specify one (or two) of these options: /N = copy NONexisting files only (cannot be used with /E or /T) /E = copy EXISTING files only /T = latest TIMESTAMP determines files sent The /N option will prevent all existing files from being overwritten. The /T option will allow overwrites only when the copy sent has a more recent timestamp. The /ET combination is especially useful for selective backup purposes: it transfers only more recent copies of files that already exist. These options can be specified only on the client or sending end. Example: if you want to make the contents of two nearly identical directories exactly so, do one transfer "*.* /T" each way; or use "*.* /N" instead if you want differing versions of individual files to remain so. (In menu mode, you can select "O"ptions for a help message describing the file selection options, including /N,E,T.) ---------------------- E. BACKING UP ALL SUBDIRECTORIES --------------------- In many situations, you may have (or want to have) a similar directory structure on two computers. While you could use the above methods to produce this result one subdirectory at a time, ZIP offers an option to do this automatically. In either menu or command-line mode, specify: /S = process all SUBDIRECTORIES Like the /S switch of the DOS XCOPY command, this causes the given command to be processed on files in the specified directory, and then also in all its subdirectories. The source directory, whether default or specified, is put in correspon- dence with a destination directory, which if not specified defaults to the same name as the source (note: NOT to the usual default directory!); and ZIP will either seek or create subdirectories of the destination directory to match those of the source. Thus, if the two computers have the following directory trees: Sender: C:\ Receiver: D:\ \WORK \BACKUP \PROG ... \ACCT \OTHER \GAMES ... then the command "ZIP C:\WORK\*.* /S[D:\BACKUP]" will begin by transferring files from C:\WORK to D:\BACKUP, then from C:\WORK\PROG to D:\BACKUP\PROG, etc. If any target directory (like D:\BACKUP\PROG) does not already exist, the /A option will cause it to be created; otherwise, the operation will simply terminate with an error message. The /S option can be combined with any of ZIP's other file transfer options. It is most commonly used for backup purposes either together with /A, when you are trying to establish a corresponding directory structure in the first place, and want the required directories to be created; or after that, with /T, to back up files within those directories according to their timestamps. Use of complete directory specifications (including drive and path) is recommended with /S to avoid unanticipated results. If your attempts to transfer with /S repeatedly fail, matching subdirectories probably don't exist; make sure you have the "Add directories" option /A set. Consider carefully before using /S to transfer the entire contents of a hard drive, beginning with the root directory, from one hard disk to another. Critical DOS files in the root directory such as AUTOEXEC.BAT, CONFIG.SYS, and COMMAND.COM may be overwritten by those from the other computer. ------------------- F. DIRECTORY, DELETE, AND LOG COMMANDS ------------------ When ZIP is in menu mode, it offers functions for file directory and deleting, and logging into a new directory, allowing simple file maintenance (DIR, DEL, CHDIR) without exiting ZIP.COM. Whether or not ZIP will show or delete DOS Hidden or System files, and whether it will delete Read/only files, are user-configurable options. These functions can also be applied to the other computer if it has ZIP running in server mode; see SERVER DIRECTORY, etc. Directory The "D"irectory function provides an alphabetized file listing for your reference, and shows the free space left on the disk (unless this is greater than 64 MB). You will be prompted for the files to list. If you just press [Enter], ZIP lists all files (*.*) in the default directory. Subdirectory names, if any, are preceded by a backslash "\". Delete The d"E"lete function prompts for a filespec to delete; as always, a path and/or wildcards may be included. It accepts only a single filespec, not a list of them. Deletion is immediate; be careful, especially when using wildcards. Log Although you can always type the full path information for any files you want to look for or transfer, if you're going to be working in a different directory for a while, it can be more convenient to change ZIP's default directory. In menu mode, the "L"og command will let you do this; you will be prompted for the new drive and/or directory, or you can just press [Enter] to check the current directory. Initially, of course, the default is the current DOS directory. If the directory you specify does not exist, and the /A option is in effect, ZIP will create it. (The Log command works much like the DOS commands CHDIR/MKDIR, except that ZIP does not actually change the current DOS directory, it simply keeps its own record of the directory you want to be working in.) ------------------------ G. WAITING FOR A CONNECTION ------------------------ Normally, once a process is initiated (file transfer, directory request, etc) ZIP will wait indefinitely until a connection with another copy of ZIP is established on the selected port. As soon as the corresponding process is initiated on the other end, the operation will proceed. However, in some circumstances this behavior may not be desirable: for example, a batch file containing ZIP commands would stall if ZIP was not found running on the other end in server or receive mode. So an option is provided to have ZIP give up and exit (returning a Connect Error) if a connection is not promptly established. In menu mode, just select "P"arameters, then press "X" and select an exit time (0-9 min). On the command line, specify the option: /Xn = eXIT if no connection after n minutes (0-9) If "n" is not specified, it defaults to 0, meaning no waiting at all. The /X option cannot be used with server mode, which always waits indefinitely. =============================== 4. SERVER MODE ============================== In most situations, it would obviously be easier to transfer files if you could do all the typing from one keyboard, and "server mode" lets you do just that. ZIP can remain on line on one end, ready to obey instructions from the "client" computer automatically. To enter server mode: in menu mode, just choose ser"V"er. On the command line, specify the option: /V = SERVER mode and if you want, a new default directory for ZIP operations in brackets: C> zip /v[DFLTDIR] Otherwise, the default is the current DOS directory. ZIP will now wait to receive commands (described below) from the other computer. When you are finished, you can press Escape, ^C, or Ctrl-Break to exit server mode. Alternatively, you can give an instruction to terminate server mode from the other (client) keyboard. In menu mode, choose "U"nlink before quitting. On the command line, specify the option: /U = UNLINK server This option can be combined with any other ZIP function (such as a file send); the server is unlinked once the operation is complete. ----------------------- A. SENDING AND FETCHING FILES ----------------------- When one copy of ZIP is running in server mode, it is ready to accept any files that you transfer to it from the other (client) keyboard; these will be received on the server end, into any directory specified by the sender, or the server's default directory. You can also command the server to send files to you. In menu mode, just select "F"etch (not Receive), and you will be prompted for the files to fetch and a directory to put them in. On the command line, specify the option: /F = FETCH specified files from server and, if you want, a directory to put the received files in: C> zip FILESPEC /f[DESTDIR] Otherwise they will be put in the current directory. If the desired files are not located in the default directory on the server, you must specify the (server's!) path as part of the "FILESPEC" to fetch. Any of the selection options (/N,E,T,P) or directory options (/A,S) may be used. --------------- B. SERVER DIRECTORY, DELETE, AND LOG COMMANDS --------------- If your other computer is running ZIP in server mode, you can also request a directory from it, delete files on it, or log a new directory on it. In menu mode, when using the "D"irectory, d"E"lete, or "L"og commands, simply type a ">" before an argument to indicate that it applies to the server. This can be done either alone, or following a request on the client end: Directory: \WORK\*.BAK client alone Delete: >B:\BACKUP\OLD.FIL server alone Log: \WORK >B:\BACKUP both As a convenience, since the two computers may have a similar directory structure, you can also type a quote mark (") to log the same default directory for the server. Log: >" ...logs same dir on the server as client Log: C:\WORK >" ...logs C:\WORK on both Log: C:\WORK >D:" ...logs D:\WORK on the server On the command line, you can specify one of the options: /D[FILESPEC] = Directory listing on server /K[FILESPEC] = Kill (delete) file on server /L[NEWDIR] = Log new directory on server /D alone lists all files "*.*", or it can be followed by a filespec in brackets, like "/D[\*.BAT]". /K requires a filespec in brackets; note also that "K" differs from the equivalent menu mode command letter, d"E"lete. Directory and deletion requests accept only a single filespec, not a list of them. Deletion is immediate; use caution, especially with wildcards! ---------------------- C. COMPARING DIRECTORY CONTENTS ---------------------- If your other computer is running ZIP in server mode, you can also compare the contents of directories, showing files that appear in one but not the other, or that exist in different versions. (This can function as a preview of what files will be transferred if you use the /N or /T option.) Common identical files are not shown. In menu mode, just choose "C"ompare. You will be prompted for the files to compare. If you just press [Enter], ZIP compares all files "*.*" in the default directory on each end. Type a ">" if you want to specify a different directory on the server: Compare: >\BACKUP client *.* with server \BACKUP\*.* Compare: *.DOC client *.DOC with server *.DOC Compare: *.DOC >\BACKUP client *.DOC with server \BACKUP\*.DOC ZIP will produce two listings: first files on the client end that don't match up with those on the server, and then vice versa. If a file appears on both ends, but in differing versions, it will be flagged with a "+" or "-" to indicate which appears to be the later (+) or earlier (-) version, according to the files' timestamps. This is more efficient than simply displaying the full directory contents on both ends, as most other programs do. Alternatively, on the command line, you can specify the option: /C = Compare with server All files "*.*" are compared, unless you provide a filespec. The option can be followed by a directory in brackets: C> zip FILESPEC /c[SRVRDIR] otherwise, the default directory on the server is assumed. --------------------------- D. SERVER TIME COMMAND -------------------------- For an explanation of why you should keep your computers' clocks in agreement, see CLOCK SYNCHRONIZATION. When your other computer is running ZIP in server mode, you can perform an exact synchronization with one simple command. In menu mode, select "T"ime. The current system time (and date) will be displayed, and you will be prompted in a manner much like the DOS command TIME: To synchronize, enter new time or press ENTER: You can also press Esc (as always) to quit. Time can be entered in either 12 or 24-hour format, as desired. ("1:47pm" is equivalent to "13:47".) Performing this function periodically is an easy way to ensure that your computer clocks remain in agreement. (Note: this function resets the date as well as the time on the server to match that on the client computer, shown; but it does not accept date corrections. If necessary, exit ZIP and use the DOS DATE command.) ========================== 5. FURTHER USAGE NOTES =========================== A. SUMMARY OF OPTIONS The following options may be used in either menu or command-line mode: /E,N Existing, Nonexisting files only /T more recent Timestamp only /P Prompt to confirm each /S process Subdirectories These command-line options are replaced by menu choices in menu mode: /R "Receive" files /F "Fetch" from server /V "serVer" mode /D[fspec] "Directory" from server /L[dir] "Log" dir on server /K[fspec] "Delete" files on server /C[dir] "Compare" with server dir /U "Unlink" server /1-4 port COM1-COM4 \ /Bnn speed 2400-115200 Bps \ "Parameters" /Xn eXit time 0-9 sec / /A Add new directories / /? "Options" This option is available only on the command line: /M Monochrome (DOS) output This command is available only in menu mode: "Time" synchronization These settings are available only from menu mode "Parameters": include Hidden, System files preserve Archive status overwrite Read/only files --------------------- B. EXAMPLES OF COMMAND-LINE SYNTAX -------------------- SENDING FILES: C> zip b:myfile *.doc send files B:MYFILE, B:*.DOC C> zip *.bak /[b:\recs] /x1 send files *.BAK to directory B:\RECS (but quit with error if no connection in 1 minute) C> zip my.* /2 /p send files C:MY.* over COM2, with prompts to confirm each file individually C> zip *.* /n send all files which don't already exist in receiver's default directory C> zip a:chapter.* /et send all files A:CHAPTER.* of which an older version exists on the receiving end RECEIVING FILES: C> zip /r /3 receive files over COM3 C> zip /rp[\temp] receive, with default directory C:\TEMP, prompting to confirm each file individually BACKING UP DIRECTORIES: C> zip \work\*.* /sa[f:\work] duplicate the entire subdirectory tree from C:\WORK on down, to receiver's drive F: ENTERING SERVER MODE: C> zip /v2b38 wait as server, at 38400 bps on COM2 C> zip /v[d:\] wait as server, with default directory D:\ EXCHANGING FILES WITH SERVER: C> zip b:\recs\my.* /f[\orig] fetch files MY.* from server directory B:\RECS into client directory C:\ORIG C> zip my.fil,my.bak /u send MY.FIL and MY.BAK to server's default directory, then unlink server FILE MANAGEMENT WITH SERVER: C> zip /d[\work\*.bak] show all server's files \WORK\*.BAK C> zip /k[junk] delete server's file JUNK C> zip *.txt /c[\mydir] compare *.TXT with server's \MYDIR\*.TXT C> zip /la[c:\recs] log server directory C:\RECS, creating it if it doesn't alerady exist ------------------------- C. AUTOMATING USE OF ZIP -------------------------- There are several ways of performing complex repetitive tasks, like backing up several groups of files, more easily with ZIP, by taking advantage of its own features (indirect filename lists in "@files") or those provided by DOS (batch files, input/output redirection). Redirected Output Standard DOS command line output redirection (">") can be used with ZIP. Thus, for example, "ZIP /D[*.BAK] >ZOUTPUT" can be used to capture the output of a ZIP directory listing in a file ZOUTPUT, to be examined or processed later. (As a side effect, nothing displays on the screen; thus you can also use ">NUL" to simply suppress output, if desired.) Note that for output redirection to work, ZIP must be using ordinary DOS output, not color output; this can be selected with the ZIPSET utility, or changed with the /M option. Redirected Input Because ZIP accepts standard DOS input redirection ("<"), you can automate a frequently performed series of tasks (sending groups of files to different directories, etc) by running ZIP in menu mode with redirected input. Redirected input is a sort of "script" describing a complex task. You will need to create a text file containing exactly the keystrokes you would use to perform a task; think about the way ZIP prompts for input, and work out your responses carefully. (Note, for example, that when you select an option like "S"end you don't press [Enter] afterward, but when you provide a filename you do.) For example, if the file Sc:\work\*.* /t "ZINPUT" contains e:\work the following text: Sc:\work\ed\*.* /t d:\ed UQ then "ZIP <ZINPUT" would back up (with the "/T" option) all files in C:\WORK to directory E:\WORK on the server end, and similarly files in C:\WORK\ED to D:\ED, then unlink ("U") the server and quit ("Q"). Any command-line arguments or options must precede the "<" redirection character. If you use the /P option while running ZIP with redirected input, you will still have to type any "Y/N" responses from the keyboard yourself. You must always end the file with "Q" to quit; DOS does not return to the keyboard for further input if the end of the input file is reached while the program is still running, so your system would just lock up without it. Indirect File Lists (@files) A number of file management and communications utilities can write a list of filenames selected according to various criteria to a file, or accept the name of such a file following an "@" sign to process all the filenames it contains; ZIP also honors this convention. You can also create such a file yourself, with any text editor, inserting the names of files which you may often want to transfer as a group. Such an "@FILE" should contain complete filespecs (with drive and path), separated by spaces and/or carriage returns. ZIP can then be used to transfer those files. For example, if file "FLIST" contains: c:\work\*.bak c:\myfile then "ZIP @FLIST" will send files C:\WORK\*.BAK and C:\MYFILE. Options can only be specified on the command line after the @file name (not within the @file), and will affect all files transferred. Batch Files Since each individual function can be performed from the command line, ZIP is easy to use in batch (.BAT) files. Batch files with multiple invocations of ZIP run a little more slowly than the other methods above, but they can contain replaceable arguments, tests for the existence of files or directories, prompts and jumps for the user to choose different courses of action, and other powerful features. See your DOS manual for details. Use of the /X option is recommended in batch files, so that an alternate course of action can be taken if a connection cannot be promptly established. You may also want to set a larger clock synch tolerance, or disable it entirely, so that /T transfers do not fail unexpectedly. If an error occurs during operation in command-line mode, ZIP sets the DOS error code, so that a batch file can test the ERRORLEVEL to determine subsequent action. Normally 0, the value returned will indicate which of the following errors occurred: 1 = argument error 8 = transmission error 2 = out of memory/too many files 16 = disk read/write error (full?) 4 = connect error/no server 128 = user abort It is always advisable to test for errors and abort execution of a batch file if an operation (upon which later actions may rely) has failed. ============================ 6. UTILITY PROGRAMS ============================ A. COPYING ZIP ITSELF WITH ZIPDUP ZIPDUP is a simple utility that makes it possible to duplicate ZIP.COM on another computer initially, when your two computers don't share a common disk format. Because this feature will be used only rarely, it's not part of ZIP itself. ZIPDUP can, in fact, transfer any file without the need for receiving software, but it's very slow and cumbersome compared to ZIP itself. To duplicate ZIP with ZIPDUP: 1. Connect the cable to the desired serial port on each computer. You must use COM1 or COM2 only; and the cable must have the DTR lines connected, as well as the data lines -- see cabling diagram under TECHNICAL INFORMATION below -- or ZIPDUP will not work. (In this event, you'll need to have a telecom program running on both computers, to transfer ZIP.COM via XMODEM or another similar protocol.) 2. Set up the receiving end: Make sure the DOS utilities DEBUG and MODE are available (either in the current directory or in your PATH); you will have to use MODE, and ZIPDUP uses DEBUG. Be certain that the last character of your DOS prompt is ">". (Yes, this actually matters!) If in doubt, type the command: PROMPT $P$G Then prepare to receive data by typing these two commands: MODE COM#:96,N,8,1 (port "#" = 1 or 2 only) CTTY COM# (Note: on some systems, like the HP100LX, it may be necessary to add ",P" to the end of the MODE command.) The CTTY command gives control to the sending computer, via the COM# port. The receiving system will seem to "lock up", ignoring any keyboard input. If the ZIPDUP transfer fails, you will need to reboot it. 3. Now, on the sending end, to duplicate your copy of ZIP.COM, type: ZIPDUP ZIP.COM (Actually, you can omit the filename if it is "ZIP.COM"; otherwise, type it.) You will be asked to specify the COM port (again, 1 or 2 only) that the cable is connected to; if the connection can be made, the transfer will proceed. When ZIPDUP is finished, you will find a duplicate copy of ZIP.COM in the current directory on the receiving computer. ---------------------- B. CHANGING DEFAULTS WITH ZIPSET --------------------- The ZIPSET utility allows you to customize ZIP to your own requirements. Certain "defaults" that are assumed unless you specify otherwise (via command-line options or menu choices) can be changed: transfer speed and port, synch tolerance, attribute handling, directory creation, and colors. Type: ZIPSET ZIP.COM (Actually, you can omit the filename if it is "ZIP.COM"; otherwise, type it.) To change your defaults, select "Edit" from the ZIPSET menu, make changes, then select "Save"; to restore the original distribution settings, select "Restore". To exit without saving changes, select "Quit". The "Edit" procedure steps through a sequence of settings you can change. For the port you may enter simply "COM1" through "COM4", or any specific hexadecimal address required by your hardware ("03F0", etc). For the speed you must choose by letter from the allowed values. For the clock synch tolerance, enter a value from 1 to 99 minutes, or 0 to disable synch testing. The next set of choices configure ZIP's treatment of DOS file attributes and nonexistent directories. You can determine whether or not Hidden or System files will be included in ZIP's operations; whether a file's Archive attribute should be preserved when it is received on the other end; whether ZIP can overwrite or delete files that have the Read/Only attribute; and finally, whether ZIP should create new directories when those you specify do not already exist. Then there is a setting to force 40-column display width. Normally this is set to "No"; you will see "Width=AUTO", and ZIP adapts itself to the current video mode (40/80 columns). Finally, ZIPSET offers you a choice of color output (via the PC BIOS) or standard DOS output. You might want to select DOS output if color output does not display correctly on your video system, or if you will want to redirect output from ZIP to a file or device (color output does not redirect). Whichever default you choose, the /M option will change to the other. If you select color, ZIPSET displays a palette and offers you a choice of text colors. ZIP uses three different colors: a "message" color, a "hilight" color for contrast, and an "active" color (during file transfer activity). Each is specified by an "attribute byte" consisting of two hex digits, for a background and foreground color. ("17" = "1", blue background, & "7", white text.) The color digits are: 0 = BLACK 4 = red 8 = GREY C = bright red 1 = blue 5 = magenta 9 = bright blue D = bright magenta 2 = green 6 = brown A = bright green E = yellow 3 = cyan 7 = WHITE B = bright cyan F = BRIGHT WHITE The palette will include 128 colors from 00-7F. Use of colors 8-F as background (80-FF) is also possible but not recommended, since on most systems this produces blinking video. Some colors may be invisible or indistinguish-able on monochrome screens, though all MDA systems can display BLACK, WHITE and BRIGHT WHITE, and in some cases GREY also. Please DO NOT distribute modified copies of ZIP.COM; this could confuse other users. (ZIPSET includes an option to restore the original default values.) ========================== 7. TECHNICAL INFORMATION ========================= A. GENERAL INFORMATION The amount of free memory ZIP requires in order to operate is displayed when the "/?" option is used. ZIP 2.01, for example, reports: "Requires 71- 120-170k RAM", meaning that a minimum of 71k RAM is necessary, 120k is recommended for 8086/286 systems, and ZIP will use up to 170k, if available, for fastest operation on 80386/486 systems. If this extra RAM is not available on 80386/486 systems, the ZIP signon message will report "(Limited memory)", indicating that optimum performance will not be achieved. When receiving data, ZIP writes to a temporary file, so as not to overwrite any existing file until the integrity of the received file is verified; there must be enough free disk space to receive the complete file. ZIP's proprietary binary transfer protocol is not compatible with those of other programs, but it does include full CRC (Cyclic Redundancy Checksum) verification on the data to guarantee accurate transfer. Be sure you are using the same version of ZIP on each end; if the protocol has been revised, a connection will not be established. Do not disturb the cable while ZIP is transferring files, as this will abort the current operation. There is no need to worry about IRQ assignments or conflicts, but do not use ZIP while another program may be accessing the same serial port. Most users also will not need to worry about "port addresses", since these have become well standardized, but some computers (including IBM PS/2's) use nonstandard addresses for the COM3 and COM4 ports in particular. Check your computer manual to be sure. The standard port addresses (assumed by ZIP) are: COM1: 03F8h COM3: 03E8h COM2: 02F8h COM4: 02E8h To modify ZIP for use with a nonstandard port address, you must enter the address itself in hexadecimal (for example, "03F0") in place of the standard entry "COM#", using ZIPSET. ZIP was designed for optimum performance in a simple DOS environment; it is also compatible with Quarterdeck's DESQview, so that multitasking will not interfere with its operation. The use of ZIP within a "DOS session" in other multitasking environments requires special precautions. Under operating systems like OS/2 or Windows, ZIP must be given a "non-swappable", "priority", or "foreground-operation" status, so that other tasks will not interrupt data transfer. If not properly configured, you may find that ZIP's performance is erratic or a slower transmission speed must be used. ZIP works well on the vast majority of systems. If you experience unresolvable conflicts with other memory-resident software, such as background processes or disk caches, do not use ZIP when that software is operating. -------------------------- B. ABOUT SERIAL CABLES --------------------------- Serial (RS232C) cabling can seem very complicated, but the simple fact is that ZIP can transfer files using ANY serial cable that you can connect to your computers! If the cable doesn't work by itself, it will work with a "null modem adapter" attached to one end; if it doesn't fit your ports, a size or gender adapter can be used. If you're shopping for a cable specifically for use with ZIP, ask for a "null modem cable" with the correct connectors to fit the serial ports you intend to use. Double-headed cables are also made, with both sizes of connectors on each end, to connect any two PC's. Null modem cables are inexpensive (often under $15) and widely available: check your local computer store, Radio Shack, or supplies catalog. For those who may be interested, here is some further information. Serial connectors come in two standard sizes, 9 pin and 25 pin; some computers have both, some only one. They may be labeled SERIAL, RS232, COM1, COM2, or COMMS. Most PC's have only one or two external serial connectors; "ports" COM3 and COM4 are usually dedicated to devices such as internal modems. Due to a peculiar choice by the designers of the original IBM PC, PC serial connectors are usually "male", meaning the socket has pins, rather than holes to receive pins. (If you see a socket with holes, you're probably looking at your parallel printer or monitor port.) So you will need a cable with "female" connectors of the proper sizes; 3 to 6 feet is a good length. Serial cables can be wired internally in various ways: a "null modem" cable, intended to connect two PC's, has the transmit and receive data lines crossed. A normal serial cable, designed to connect a PC to a communication device like a modem, has these lines wired straight through, but a "null modem adapter" can be attached to the cable to cross them. (Modems have their serial ports wired differently from PC's, precisely so that a straight- through cable can be used to connect them: in RS232 terminology they are DCE, "data communications equipment", rather than DTE, "data terminal equipment".) The simplest cables contain only three wires, these two plus a ground; some have seven, or more, for other signals used by some serial devices; it doesn't matter for use with ZIP. (Note: ZIPDUP alone does require the additional DTR connections shown below.) If you're building or testing a null modem cable, here is the wiring diagram: |--COMPUTER 1--| |--COMPUTER 2--| DB9 or DB25 DB25 or DB9 pin # 2 - - - - 3 - - connect - - - 2 - - - - 3 transmit data \ 3 - - - - 2 - - - to - - - - 3 - - - - 2 receive data > REQUIRED 5 - - - - 7 - - - - - - - - - 7 - - - - 5 signal ground / pin # 4 - - - - 20 - - - - - - - - 6 - - - - 6 * \ 6 - - - - 6 - - - - - - - - - 20 - - - 4 * \ DTR,CTS etc (optional; 7 - - - - 4 - - - - - - - - - 5 - - - - 8 / *=required for ZIPDUP) 8 - - - - 5 - - - - - - - - - 4 - - - - 7 / Use of a short, well shielded cable is highly recommended; high speed transmissions can be susceptible to RF interference. ------------------ C. USING ZIP ON HP95/100/200LX PALMTOPS ------------------ The Hewlett-Packard 95/100/200LX palmtop computers are "nearly" PC- compatible; ZIP will work on them, but there are some special considerations. You will need an Infrared-capable PC or the special HP serial cable, which is available either separately or as part of the Connectivity Pack. ZIP automatically detects the LX palmtop and its current screen size. For the LX's built-in serial port, ZIP must be set to COM1; whether the Wire or Infrared port is used depends on your palmtop's current setting (controlled by the command SERCTL /W or SERCTL /I). In either case, ZIP does power up the port on entry and turn it off again upon exit to conserve batteries, so port power can be left off in DOS. Transfer rates with the LX palmtop are typical of XT-class PC's, about 8 k/sec. HP 100/200LX The 100/200LX System Manager software can interfere with ZIP's use of the serial port, making it difficult to transfer any but the smallest files. Do not just run ZIP from Filer, or from a DOS session under System Manager. Typically, due to the complex nature of the LX palmtop, you can avoid this problem in several ways: (1) Terminate SYSMGR (from Application Manager, press MENU,A,T,Enter) and run ZIP from the DOS prompt. Type 100 or 200 to restart SYSMGR. (2) Run ZIP from Application Manager after installing it like this: Name: &Zip Path: C:\ZIP.COM |120 Comment: [Fn+!][Fn+?] The "&" lets you run ZIP by pressing "Z". The "|120" after the Path specifies a memory allocation; use the second RAM figure from the "ZIP /?" information message. An upside-down exclamation point (press Fn,!) is required at the start of the Comment field to tell SYSMGR not to interrupt ZIP. The Fn,? is optional on the 200LX, to return directly to SYSMGR when you select Quit. Note that while you are editing this AppMgr entry, you can install the included ZIP icon as well; just put ZIP.ICN in the same directory as ZIP.COM. (3) Install and use Mark Scardina's free ASERCTL utility, available on the CompuServe HPHAND forum, or on your ZIP registration disk. It not only gives you keyboard control over serial port power, but also prevents interference from SYSMGR. ZIP can then be run in any way you like. ZIPDUP requires a cable connection. In order for it to send to the 100/200LX, you must include ",P" in the MODE command in the procedure described above (MODE COM1:96,N,8,1,P). HP 95LX On the 95LX, ZIP can be run in a variety of ways, including from Filer (highlight ZIP.COM and press F4=Run) or from the DOS system prompt. File transfers can fail on early versions of the 512k 95LX due to a bug in its serial port handling. You can avoid this by performing a [Ctrl+Up+On] reset (answering "No" at the prompt, to preserve your C: drive!) before running ZIP, or (for some unknown reason) by performing a Directory request with ZIP before transferring files. Use of ZIP on the 95LX Infrared port is possible but not recommended; you must select a speed of 2400 bps, which is all it is capable of. The 95LX serial port does not allow ZIPDUP to operate; instead, to transfer ZIP.COM to the 95LX, you must use the 95LX's internal software: either the built-in COMM utility together with any PC telecom program supporting XMODEM or KERMIT protocol, or the Connectivity Pack. ----------------------------- D. ERROR MESSAGES ----------------------------- Ready / Waiting connection has not yet been established. <Argument error> invalid command-line argument(s). <Insufficient memory> not enough memory to load and run ZIP. <Connect error> can't connect -- bad cable? wrong version? timeout? <No server> function requires server mode on other computer. <Too many files> filespec includes too many files to process at once. <Error reading @file> @file nested or too large to read. <Bad directory> specified directory doesn't exist or can't be created. <Name conflict> filename is in use by a directory or read/only file. <Delete error> specified file doesn't exist, is read/only, etc. <Read error> error reading a file: access denied, etc. <Write error> error writing a file: disk full, invalid path, etc. <Aborted> you pressed Esc/^C/Ctrl-Break. <Error> communication error, or ANY error on OTHER computer. (see message on other computer for cause) Error return (ERRORLEVEL) codes are described under "Batch Files" above. ---------------------- E. ABOUT THE PROGRAM AND AUTHOR ---------------------- As of Fall 1993, ZIP has been well reviewed in numerous computer newsletters; it has been included on the HP Palmtop Paper's subscriber disk for HP95/100LX users, and on disk with the following computer books: "DOS 6.0 Power Tools" by John Goodman & John Socha (Bantam Books) "DOS Stuff Microsoft Forgot" by Tim Stanley (Que Books) "The Little Laptop Book" by Steve Cummings (Peachpit Press) "lightning fast and simple to learn... simply dazzling... ZIP provides the fastest file transfer between PC's using the tiniest amount of disk space... a simple, lean, and very effective program, not to mention the fastest of all the programs we looked at for this review." -- Bil. Alvernaz, Quantum PC Report, June 1992 Eric Meyer is also the author of the shareware VDE editor/word processor and a number of free utilities for PC compatibles. He holds an A.B. in physics and a Ph.D. in history and philosophy of science, and has taught at the Universities of Indiana, Oklahoma, and Colorado. A computer enthusiast since high school, he has programmed in languages from APL to Z80; lately he has been working mostly in 8086 assembler. In a period of escalating software complexity and prices, he still believes that useful, inexpensive software should remain available to computer users worldwide. ====================================[end]====================================