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NULU.DOC Documentation for NULU.COM as of 10/01/84 Version 1.0 NULU.COM and NULU.DOC are both Copyright 1984, by SYSTEM SOLUTIONS, P.O. Box 35972, Dallas, TX 75235. Both may be used freely for non-commercial purposes, but neither may be sold, included in a package for sale, or used as an incentive to buy, by any person, organization or corporation without prior arrangement with the copyright holder, SYSTEM SOLUTIONS, or the author of this version, Martin Murray. Furthermore, neither SYSTEM SOLUTIONS nor Martin Murray will bear any responsibility for losses resulting from the use or inability to use this program. NULU.COM may not be distributed without NULU.DOC, nor may the copyright messages be removed from either file nor caused to not be displayed. ACKNOWLEDGEMENTS This program would not have been possible were it not for the elegant work of Gary P. Novosielski and those others working with the LU library structure. INTRODUCTION NULU is offered as a complete replacement for LU and LSWEEP. Weighing in at 14k, it includes nearly all features of both programs and then some. It features: Two operation modes with a full menu for each Viewing and printing of member files, unsqueezing when necessary Extraction of member files with an option to unsqueeze where appropriate Bigger libraries, up to 800 members or more depending on available memory Automatic member sorting, all members kept sorted at all times Faster reorganization Enhanced error handling Access to deleted members Optional read only mode General compatibility with LU and NSWEEP syntax Numerous user patches DIFFERENCES BETWEEN NULU AND LU I am aware of only one thing that LU does that NULU does not do. LU maintains a CRC for each member file and for the library directory as a whole. NULU doesn't do this at all. In fact, NULU changes these CRC bytes to 00 as soon as it gets the chance. In case you still want or need to run LU on a library modified by NULU, LU will simply regard it as a library created by an earlier LU version and will promptly set CRC's for the various members. NULU To the best of my knowledge, NULU will run on any system running CP/M 2.x or higher, however it has only been tested on the Osborne 1 and the Osborne Executive computers. It is written entirely in 8080 assembly language. A complete discussion of the nature and advantages of library files is beyond the scope of my endurance, however a short recap is in order. A library file is a single CP/M file which maintains 1 or more smaller files as its members. Each file is written into the library and recorded in the library directory. After that, it may be accessed for viewing, printing, or execution, or may be extracted from the library to assume the status of a stand-alone file once again. The reasons for doing this are many. For one, under CP/M each file occupies a minimum amount of disk space. This amount can range from 1k to 16k, depending on the system. Even though a file may only be 1 byte in length, it will still occupy the minimum required amount; the rest of the space is wasted. Putting these files in a library minimizes the possible waste to 127 bytes. Each file also occupies a directory entry. On most floppy disk systems, the maximum number of files per disk is 64. By including a file in a library the directory space it used to occupy is freed for another file. Additionally, using library files can simplify the process of categorization by subsuming several files of similar types or subjects into one file. However, there are also dangers associated with using libraries. The main one is that if a library file is lost or damaged, all of the member files are lost as well. The solution to this problem can be summed up in one word: BACKUP. NULU probably isn't perfect, and we all know that disk systems aren't, so backup your important libraries, please. I don't want to hear any sad stories. Almost as important as backing up libraries is the use of discretion when deciding what to put into them. Let's face it, if a file is in a library it is not as easy to get to. If you need to get to a file every 15 minutes, it probably shouldn't be in a library except as a backup measure. AN ASIDE CONCERNING FILESPECS When specifying a filespec, wildcards may be used freely, however, unlike most programs, NULU doesn't insist that a "." separate the filename from the filetype. For example, the filespec "**" means the same thing as "*.*" to NULU. On the other hand, the filespec "FRED.TXT" should be typed in just like that. "FREDTXT" would make NULU think that no filetype had been specified. The rule is simple: use a dot any time you like, but it is only strictly necessary when it is needed for clarity. When specifying a drive and/or user area the syntax is very liberal. "A15:**" means the same as "15/A:*.*", as does "1A5:**". The colon is absolutely necessary. If a different user area is desired for the default drive, the drive specifier may be omitted, as in "15:**", just as the user area may be omitted as in "A:**". If a drive/user specification is made, but no filespec is indicated, a filespec of ????????.??? is generated. Therefore to indicate the default drive, current user area, and a filespec of ????????.???, just type a colon by itself (e.g., ":") ! NULU OPERATION NULU may be invoked with or without a command tail. A command tail can consist of any combination of valid NULU operators up to 128 characters (the limit imposed by the CCP. Once NULU is running, command lines can be as long as 254 characters.) As in LU, all NULU commands are preceded by a dash. This is a copy of the menu for the command mode of operation: -A Add members -B Brief toggle -C Close the library -D Delete members -E Extract members -F Filesweep mode -G Get filespec -K Krunch the library -L List members -M Menu -N Rename members -O Open a library -P Print members -Q Unsqueeze members -R Replace members -T Replace/Add members -U Drive/User change -V View members -X Exit NULU -Y Disk directory -< Redirect input -> Redirect output Commands may be strung together, each terminated by a space. They are processed left to right. All characters are converted to upper case. The default drive/user area are displayed along with the name of the current command mode each time the console is prompted for input. The commands will be explained in order of their appearance above. All items in [square brackets] indicate optional parameters. Filespec parameters enclosed in (parenthesis) indicate references to deleted member files. Three dots ("...") after a parameter indicate infinite repetition. COMMANDS -A ADD MEMBERS Syntax: -a filespec[ filespec...] Use this command to add files from disk to the current library. NULU will make a series of passes through the directory, adding files as it goes, until the list of matching files is exhausted. If matching filename already exists as an active member in the library, its name will be displayed and the file will not be added. In all file addition and replacement operations, if a deleted entry of identical size can be located, that disk space and directory entry will be used rather than allocating new space for the file. This means that it will be necessary to reclaim wasted disk space less often. -B BRIEF TOGGLE Syntax: -b This toggles the prompting mode. The release version of NULU is setup to print the full name of the current mode for a prompt, as in "-ADD MEMBERS A0:>". If BRIEF is turned on the user will simply see "-A A0:>". NULU may be permanently patched to default to BRIEF ON or OFF. See NULU MODIFICATION. -C CLOSE THE LIBRARY Syntax: -c This command closes the current library, writing its directory to disk if any changes have been made to the directory. The library directory is NEVER written except when the library is closed, so be sure to do it. If you forget to do so and remove the disk, NULU will prompt you for the disk again and will attempt to recover, but no guarantees! Some other operations that cause the current library to be closed are: -k, -o, -x -D DELETE MEMBERS Syntax: -d filespec[ filespec (filespec)...] Member files matching the given filespec will be given deleted status in the library directory, except when the filespec is enclosed in parenthesis. In that case matching deleted members will be given active status. That is, they will be undeleted. If the filename of a matching deleted member file already exists as an active member, the filename will be displayed and the file will not be undeleted. -E EXTRACT MEMBERS Syntax: -e filespec[=newfilespec filespec...] Use this command to extract active member files. If extraction to the current drive/user area is desired, no further syntax is necessary. To indicate another drive, however, a destination filespec may be included following an equals sign. Example: -e **=a5: would extract all active members to drive A, user area 5. Files may be renamed as well as redirected by indicating a filespec along with, or in place of, a drive user specification. Examples: 1. -e *asm=*bak 2. -e *asm=5:*txt 3. -e fred.txt=sam.txt jane.inf=c8:girls.dbf The examples would produce the following results: 1. Extract all files with a type of .ASM to the default drive/user renaming them with the filetype of .BAK. 2. Extract all files of type .ASM to user area 5 of the default drive, renaming each with the .BAK filetype. 3. Extract the member file FRED.TXT to the default drive/user under the name of SAM.TXT, and extract the member file JANE.INF to user area 8 of drive C: with the filename GIRLS.DBF. The only rule to remember is that if a destination filespec is entered it cannot be any less ambiguous than the source filespec. That is, "*asm=*bak" is valid while "**=*bak" is not valid. -F FILESWEEP MODE Syntax: -f This command places NULU in its second operational mode: the filesweep mode. This allows the user to move through the directory of active member files as if they were individual files being examined by a program like NSWEEP. The filesweep mode's command list is as follows: A Next member B Previous member C Close the library D Delete member E Extract member L Log new library P Print member Q Unsqueeze member R Rename member U Drive/User change V View member W Wildcard rename X Exit NULU Y Disk directory Z NULU command mode ? Menu Because of the extreme similarity between these commands and the commands of NULU's command mode, only a short description of each command will be given. A -- Advance to next member (spacebar, cr, or lf will produce the same result) B -- Back up to previous member C -- Close the current library D -- Delete current member file E -- Extract current member file (prompt allows redirection) L -- Logon to new library (closes the current library) P -- Dumps the current member file to LST: (unsqueezes if needed) Q -- Extract current member file, unsqueezing if necessary (prompt allows redirection) R -- Rename current member file U -- Change drive/user defaults (returns file pointer to the top of the file list) V -- View current member file (unsqueezes if needed) W -- Wildcard rename of members (prompts for both oldname and newname) X -- Exit NULU (closes all files) Y -- Get disk directory for default drive/user (returns file pointer to the top of the file list) Z -- Return to NULU command mode (current library remains open) ? -- Print the filesweep mode menu (returns file pointer to the top of the file list) If, when the filesweep mode is entered, or after a library has been closed, there is not a library currently open, the filesweep mode will prompt with: No library open. and will accept only the following commands: L,U,X,Y,Z,? Likewise, if a library is open but only has a directory with no other active members, the message No member files. will be printed and only the commands listed above will be accepted. During the filesweep mode operation, each file will be listed in the order in which it is found in the directory, along with the size in K that the file would occupy if it were extracted to the default drive. If the filesweep mode is terminated by a return to the NULU command mode, any commands that followed the -F command on the previous NULU command line will be executed. -G GET FILESPEC Syntax: -g filespec NULU will search for the filespec indicated. If it is found, processing continues. If not, the user is prompted to insert the disk containing that filespec. The drive is then reset and search again. The program will prompt forever until it receives the proper filespec or until a cntrl-c is entered, forcing NULU to continue without the filespec being found. This command can be useful when attempting to control NULU through a submit utility like DRI's SUBMIT.COM. For example, one might type: nulu -o a:asm -g b5:-work.005 -e **=b10: -g a0:-5.005 -x After loading, NULU would open a library called ASM.LBR on drive A: in the current user area. Next it would search user area 5 of drive B: for filespec -WORK.005 until it was found. Then all active member files would be extracted to user area 10 of drive B:. Finally, NULU would search user area 0 of drive A: for a filespec called -5.005 until found. Then NULU would terminate. Notice here that the ASM.LBR didn't have to be closed before the search for the final filespec because no change had been made to the library directory. If a change had been made, after the new filespec had been loaded, NULU would have demanded the disk with ASM.LBR back so it could update the directory. Therefore the GET operation would be effectively negated. -K KRUNCH THE LIBRARY Syntax: -k[ <number of entries to allow] Even though all members are kept in alphabetical order at all times, when a member is deleted the disk space it occupies is not released to the operating system until the KRUNCH command is executed. KRUNCH consists of the following steps: 1. The library directory is re-sorted by sector index number, that is, in the order in which the member files actually exist in the library. 2. The library is closed. 3. A new library called WORKLBR.$$$ is opened in the default drive/user area and the user is prompted to input the number of files that the new library should be able to contain. If the user wants just enough entries to contain the currently active members, the number 1 or any number less than or equal to the current number of active entries may be entered. If the optional parameter listed above is entered, it will be used as the number of entries. (The KRUNCH processed may be aborted here by typing RETURN or 0. Please note that the library directory counts as an entry and will automatically be accounted for by NULU.) 4. Once WORKLBR.$$$ is opened, the active member files from the original library will be copied one by one into the new library. The copy routine uses a recursive process to copy as many files at one time as possible. 5. The old library is deleted and WORKLBR.$$$ is renamed with the old library name. Examples: 1. -k 2. -k <1 3. -u b5: -k <63 4. -u b5: -k <1 -u a0: -k <63 The above example would produce the following results: 1. The library would be KRUNCHed to the default drive/user area. The user would be prompted to input the number of entries to allow. 2. The library would be KRUNCHed to the default drive/user area with just enough entries to contain all currently active member files. 3. The default drive/user area would be changed to B5: before the KRUNCH begins. Then the library would be KRUNCHed, allowing 63 entries. 4. The default drive/user area would be changed to B5: before the KRUNCH begins. The KRUNCH would commence, allowing only enough entries to contain all active members. The drive/user area would be changed to A0:. Then the library would be KRUNCHed again, allowing 63 entries. -L LIST MEMBERS Syntax: -l[ filespec] Syntax: -l[ (filespec)] Use this command to list the contents of the library directory. Each member filename will printed followed by the starting relative sector number in the library file, the size of the member in sectors, and the size in K that the file would occupy if it were to be extracted to the default drive/user area. Finally, a recap of the size of all member files listed is printed, along with the number of sectors occupied by deleted files. The parameters listed above can be used to control the selection of files for display. Examples: 1. -l 2. -l ** 3. -l (**) 4. -l *asm 5. -l (fred.txt) The above examples would produce the following results: 1. All active member files listed. 2. All active member files listed. 3. All deleted member files listed. 4. All active member files matching the filespec of ????????.ASM listed. 5. All deleted member files called FRED.TXT listed. (Note that is IS possible to have more than one deleted file with the same name.) -M MENU Syntax: -m Print the command mode menu. -N RENAME MEMBERS Syntax: -n oldfilespec=newfilespec[...] Syntax: -n (oldfilespec)=newfilespec[...] This command is used to rename active or deleted member files. Wildcards are fully supported, but the newfilespec can be no less ambiguous than the oldfilespec. Deleted members may be renamed by enclosing the oldfilespec ONLY in parenthesis. Examples: 1. -n *asm=*bak 2. -n (fred.txt)=sam.txt 3. -n **=** The above examples would produce the following results: 1. All active members matching the filespec ????????.ASM would be renamed with a filetype of .BAK. 2. The first deleted member file called FRED.TXT would be renamed to SAM.TXT. All other members matching that filespec would be listed along with a message indicating that they could not be renamed. 3. All active member files would be listed, each with a message indicating that they could not be renamed because the name already exists. -O OPEN A LIBRARY Syntax: -o filename[ <number of entries to allow] With the exception of the filesweep Logon command, this command is the only method to open or create a library. NULU will search for the filename indicated. If it is found, it will be opened and a message will be displayed indicating the size of the Data Transfer Buffer. This is the number of sectors in memory that NULU will have to use in extracting, adding or copying member files. If the file is not found, the user will be prompted for the number of entries to allow in the new library. If the optional parameter above is passed, the number will be used to determine the directory size of the library. All directories can contain some multiple of 4 entries. All numbers input will be rounded up to the nearest multiple of 4. Remember that the directory itself counts as one entry and that NULU will automatically make space for it. The filename passed must be unambiguous. NOTE ON DIRECTORY SIZE: Depending on available memory, libraries with as many as 1250 entries (theoretically) can be opened. But watch the Data Transfer Buffer Size! If it is less than 8 sectors you will not be able to unsqueeze any files. -P PRINT MEMBERS Syntax: -p filespec[ filespec (filespec)...] With this command, the ascii contents of member files matching the filespecs given will be dumped to the list device. If the file is squeezed, NULU will unsqueeze it. Deleted members may be listed by enclosing the appropriate filespec in parenthesis. -Q UNSQUEEZE MEMBERS Syntax: -q filespec[=newfilespec filespec...] This command is identical in operation and syntax to the EXTRACT command, except that if the matching members are squeezed, they will be unsqueezed. -R REPLACE MEMBERS Syntax: -r filespec[ filespec...] This command is identical in operation and syntax to the ADD command, except that matching files will be added to the library ONLY if they already exist in the library. They will be deleted, then the new files will be added. -T REPLACE/ADD MEMBERS Syntax: -t This command is a combination of the ADD and the REPLACE commands. If the files do not exist in the library, they will be added. If they do exist, they will be replaced. -U DRIVE/USER CHANGE Syntax: -u new drive/user Use this command to change the default drive/user area. A colon (":") must follow the drive/user spec. Example: -u a5: would switch the default drive/user area to A5:. -V VIEW MEMBERS Syntax: -v filespec[ filespec (filespec)...] This command will list the ascii contents of all member files matching the given filespec to the console device. Deleted members may be indicated by enclosing the filespec in parenthesis. If the member files are squeezed, they will be unsqueezed. At each page, NULU will accept one of the following commands: 1. Cntrl-x to skip to the next member file 2. Cntrl-c to abort further listing 3. L to list one line 4. CR, space, or LF to list another full page At the end of each member file the message "Press RETURN" will be displayed and NULU will wait for a keystroke before moving to the next matching member file. -X EXIT NULU Syntax: -x[ "$$$.SUB command line"] This command will set a flag indicating that when the current NULU command line is exhausted, NULU should terminate. But the command is actually a toggle. If it is entered twice on a line the effect of the second issuance will be to negate the first. If the optional parameter is passed, it will be written to a file called $$$.SUB on drive A: in the user area that was active when NULU was first loaded. The line will be encoded as a SUBMIT command line recognizable by the CCP. Therefore, when NULU exits, the CCP will reach into that file and execute the line. (CP/M Plus users take note: the $$$.SUB file will be written to the drive that was the default drive when NULU was first loaded.) Examples: 1. -x 2. -x -x 3. -x "nsweep b:" The above examples would produce the following results: 1. The termination flag will be set and NULU will terminate when the current command line is exhausted. 2. The termination flag is set and the reset. NULU does not terminate. 3. The termination flag is set and a file called $$$.SUB is created on the appropriate drive with the command line "NSWEEP B:" encoded in it. -Y DISK DIRECTORY Syntax: -y[ filespec] This command will print an unsorted directory of the disk indicated by the parameter passed, or a complete directory if none is passed. The scope of the directory may be limited by indicated the appropriate ambiguous filespec. -< REDIRECT INPUT Syntax: -< filename This command will cause NULU to open the filename indicated and begin accepting commands from it instead of receiving them from the console. This type of file is, in effect, a NULU command file. Syntax of the commands in this file is identical in every way to the syntax used in normal NULU operation. Each command line in the file must be terminated by a CR,LF. If another "-<" command is encountered in the file, the current command file will be closed and the new one opened. After the commands have been completely processed, control will be returned to the console. All command lines will be converted to upper case and echoed to the console before processing. Any commands appearing after a "-<" command will be ignored. The filename passed must be unambiguous. -> REDIRECT OUTPUT Syntax: -> filename Syntax: -> With the first form of this command, NULU output will be sent to the filename indicated. If the file already exists, it will be deleted. All special characters that the user may have patched into NULU (see below, NULU MODIFICATION) will be sent to the file as well, with the exception of the EOF character, 26 (1ah). The only output not echoed to the file will be output caused by viewing or printing a member file. The filename passed must be unambiguous. Under the second form of this command, the current output file, if any will be closed. When NULU is caused to terminate, the current output file is closed along with the current library, if any. ERROR MESSAGES All NULU error messages are of the form: ERROR XX: Explanation where "XX" is some number from 0 to 255 and "Explanation" is a clue as to the nature of the error. Each error message is listed below, along with an explanation. Suggestions about ways to handle the error are given when appropriate. ERROR 63: ambiguity error Problem: This means that you entered an ambiguous filespec where an unambiguous filename was required. ERROR 68: disk full Problem: The library disk became full during file addition or KRUNCHing or the destination disk of an extraction command became full. Solution: If the error occurred during KRUNCHing, NULU should have recovered by itself, reopening the old library. If it did not recover, then you removed the original disk before the KRUNCH was complete or a serious read error occured. If the error occurs during file addition to the library, operation should not be impaired, but no files that required additional disk space can be added to the library. Note that deleted entries can still be overwritten by incoming files as long as the file sizes match. The original file that caused the error will be recorded in the library directory as a deleted entry. If the error occurs during file extraction or unsqueezing the destination file is deleted because it is an incomplete file. Extraction can continue as before. ERROR 73: invalid drive Problem: An invalid drive for your system was chosen (see below, NULU MODIFICATION) or a letter higher than "P" was indicated. Solution: Choose another drive or re-patch NULU. ERROR 77: not enough memory Problem: An attempt was made to open a library with a directory too large to be accounted for with available memory. Solution: Open the library on a computer with a larger TPA and reorganize it so it can be handled by the smaller system. ERROR 78: user cancel Problem: No problem. NULU is simply letting the user know why an OPEN LIBRARY or KRUNCH operation has been cancelled. ERROR 83: no directory space Problem: An attempt was made to create a file on a disk with no free directory entries. ERROR 85: file not found Problem: The filespec indicated for some operation could not be located. ERROR 86: CP/M 2.x or higher required Problem: An attempt was made to run NULU on a system with an CP/M version number of less than 2.0. ERROR 88: seek to unwritten sector Problem: A sector required to gain access to a file is indicated by CP/M to be unwritten. Solution: The library directory or perhaps the library itself has become trashed at some point. Deleting the entry and KRUNCHing will probably render it harmless, but the safest course to take is to obtain a fresh copy of the library. ERROR 100: bad library directory Problem: The file specified could not be opened as a library file. Solution: The directory could be bad, but most likely the file simply isn't a library. Check it out with some disk editor like SPZ or EDFILE. ERROR 115: bad syntax Problem: Improper syntax was user to attempt some operation. ERROR 116: squeeze decode table Problem: A file has a squeeze decoding table, but at some point the table is trashed or perhaps is missing. Solution: None really; get a new copy of the file. ERROR XX: undefined Problem: Unknown. Solution: Write down all information presented on the terminal. The number following the word ERROR is especially important. Get the information to me. Mail it or call and I will try to help. NULU MODIFICATION Patches will be listed in the order in which they appear in NULU.COM. Each patch is explained and the default values are listed immediately next to the patch address. All addresses are absolute hexadecimal. Patch Default Explanation 00171h 00h Non-zero makes NULU use the Z80 instructions LDIR and LDDR for data movement. 00172h 50h Number of characters each full video line can contain. Not necessarily the same as the number you can see. 00173h 50h Number of characters visible on a line at any one time. 00180h 10h Number of contiguously numbered disk drives in your system. If you have drives A and B, set this value to 2. It will prevent you from accessing an invalid drive. 001c5h 00h Set to a non-zero value to make NULU READ/ONLY. No operators will be executed that could change the library directory in any way. 001c6h 00h LU.COM was set up to exit automatically if a command tail was used when LU was invoked. With the release version of NULU, it takes the -X command to exit. Set this byte to a 01h to get it to act like LU in this respect. That is, it will automatically exit after executing the passed command tail, if one was present. 001c7h 01h Set to a 00h to start NULU with BRIEF mode ON (long messages not printed). 001c8h 00h Starting here are 39 bytes in which any valid NULU operators may be stored. This line will be automatically executed when NULU is loaded, even before any other parameters passed on the command line. This might be used to create a version of NULU that, after loading, sets the drive/user defaults to B0:, prints the menu, scans the drive for library files, then switches to the open library mode. That command line would look like this: -U B: -M -Y *LBR -O Notice that all characters in this line MUST be UPPER CASE. The entire line MUST be terminated by a null byte. Only 39 bytes are available for text...not a byte more. The 40th byte is for the null terminator. 03103h 0ah If you have trouble thinking in decimal, you can change this byte to get NULU to output all numbers in whatever base you please, from 2 to 24h (36d). 03825h 0005h This is the address of the BDOS vector. All operating system calls go through this address. If you have some weird, non-standard CP/M implementation you can patch this to try to make NULU work with it. 03876h 3ch This is the number of lines that NULU will print on each page during member file printing. Change this value in accordance with the line printer patch below. Starting at 03848h are 6 data areas used to define strings needed to control the console attributes. Each string is preceded by a byte indicating its active length. Then 5 bytes are available for each definition. Therefore a total of 6 bytes is consumed for each video control. The attributes are, in order: DIM or REVERSE VIDEO ON (DIM is preferred) DIM or REVERSE VIDEO OFF UNDERLINING ON UNDERLINING OFF CURSOR POSITIONING (not used in NULU) CLEAR SCREEN Each control becomes active as soon as it is patched in. Likewise, there is one string defined for the LST: device that will be issued immediately before printing a file. It begins at 038adh and has the same format as the strings above. FINAL NOTES Please report any bugs or problems to Martin Murray, P.O. Box 35972, Dallas, Tx 75235 or call (214) 351-6117. əəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəəə