Informática Multimedia 1995 April

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Text File | 1988-10-30 | 16.3 KB | 389 lines

Nifty James' Famous Sort Tool Version 1.00 of 08 May 1988 Version 1.05 of 19 May 1988 Version 1.10 of 03 July 1988 Version 1.11 of 30 October 1988 (C) Copyright 1988 by Mike "Nifty James" Blaszczak REDISTRIBUTION OF THIS PROGRAM WITHOUT THE PRIOR WRITTEN CONSENT OF THE AUTHOR IS STRICTLY PROHIBITED. THIS PROGRAM MAY NOT BE RESOLD OR OFFERED AS INSENTIVE FOR PURCHASE WITHOUT THE AUTHOR'S KNOWLEDGE. THE AUTHOR IS NOT RESPONSIBLE FOR DAMAGES, DIRECT OR CONSEQUENTIAL, CAUSED BY THE APPLICATION OR MISAPPLICATION OF THIS PROGRAM. It is very often necessary to sort information. It makes the retrevial of information more rapid, and gives the data a more humanized look. It also facilitates maintenance of lists. Thus, having a powerful sorting tool is essential to good productivity. This program is capable of very large lists, and is limited only by the availability of storage space. It runs very quickly, using optimized C code and hand-written assembly language for the more crucial routines. Using NJSORT is quite easy; it is run from the command line using a traditional syntax: NJSORT <infilename> [<outfilename>] [<options>] <infilename> is the name of the input file -- the file to be sorted. It must be present. If it is not, NJSORT will show its usage and syntax and terminate. <outfilename> specifies the name of the output file. If this name is not present, NJSORT will write the sorted output to the same disk and directory as the input fille, but will change the extention to ".BAK". For this reason, you must specify an alternate output file name if you would like to use NJSORT to sort a file with the extention of ".BAK". <options> is a list of options. These are the valid options: /B Strip blank lines from the input. If a line is found to have nothing on it, or only tabs and spaces on it, NJSORT will remove it from the output file if this option is specified. /C Case Insensitive sort. This will tell NJSORT not to pay attention to the case of the text it is sorting. NJSORT will consider "lowercase" equal to "LOWERCASE", for example. /D Remove duplicate lines. This will cause NJSORT to remove identical lines from the output. If /C is specified, the comparison for duplicate lines will not be case sensitive. If /I is specified, the check for duplicate lines will not pay attention to leading whitespace. /I Ignore leading whitespace. This will cause NJSORT to ignore the tabs or spaces at the beginning of a line. /R Sort in reverse order. Normally, NJSORT sorts starting with the lowest ASCII code and going up. Thus, 'A' comes before 'Z'. If this option is specified, NJSORT will sort starting with the highest ASCII code and going down: 'Z' will come before 'A'. /V Display sort statistics. This verbose mode will display information about the sorting process after it has completed. Normally, NJSORT sorts ASCII files by looking at each line as a separate item. Often times, there may be more than one sort field on each line. It may also be desirable to sort the text based on the content of a certain colum or field of data. To make use of this feature, these options may be used: /F# Specify the first key field number /S# Specify the second key field number /T# Specify the third key field number /Q# Specify the fourth key field number /P# Specify the fifth key field number /M, Specify field delimiter /N Sort by columns and not fields These options define the fields to be used, and their respective "weight" in the sort. When no fields are specified, NJSORT uses the entire line starting at the beginning as the sort key. When a key field is specified, NJSORT checks them in order. If the first key field of two items are equal, then the second key field is checked. If the second key field is equal, then the third is compared, and so on. If all the specified key fields are equal, or there are no more key fields on the line, the items are assumed to be equal and their final order is arbitrary. Since I maintain a database of the records in my collection, I have an ASCII file with this format: <artist>,<album>,<song>,<length>,<sidecut>,<copyright> A typical entry might look like this: Pink Floyd,Dark Side of The Moon; The,Money,6:23,0201,73 I can sort this database using the command NJSORT MUSIC.DAT /F1 /S2 /T3 /Q5 /F6 /M, /C This uses the /C option to make the sort case insensitive; thus, "PINK FLOYD" will be equal to "Pink Floyd". The program is told which keys to order the sort with, and it is told that the comma spearates the felds of data. Thus, when NJSORT sees the line in the file, it looks at it like this: Pink Floyd,Dark Side of The Moon; The,Money,6:23,0201,73 Field 1 | Field 2 | 3 | | 4 | 5 When it sorts the file, the list will be ordered by the name of the artist. "Pink Floyd" will come before "ZZ Top". If NJSORT finds that the first field of two items are equal, it will check the second field. "Dark Side of The Moon; The" comes before "Wall; The", even thoug they are both Pink Floyd albums. If the program finds that the album names in the second field are equal, it will check the third field, which is the song title. In the unlikely event they are also equal, the program will also go on to check the side and cut of the song on the album, and finally the copyright date of the song. This allows you to sort with multiple keys on fields with variable length. If the file, however, is listed in columns, for example: Pink Floyd Dark Side of The Moon; The Money Pink Floyd Dark Side of The Moon; The Eclipse . . . NJSORT should be given the option /N, which tells the program to use the numbers provided ot the key field options as column numbers. So, to sort the above file, one would use NJSORT MUSIC.DAT /F1 /S16 /T45 /C /N NJSORT will reguard the field starting in the first colum as the first sort key. The second key will start in column 16, and the third key starts in column 45. To have NJSORT regard these numbers as column numbers, the /N option must be specified. With Version 1.10, NJSORT also has the ability to sort binary files that contain fixed-length records. You can specify the offset of the sort keys in each record using the /F, /S, /T, /Q, and /P options, as normal. You must also specify the /W option. The /W option must be immediately followed by the number of bytes in each record of the input file. NJSORT will sort the records, and will write out a binary file of the same format -- just the records will be rearranged. If NJSORT can't read a full record, it will stop and print an error message. Using NJSORT is as simple as that, even for all its power and versatility. NJSORT will read the datafile when it is invoked, and will then attempt to sort all the information in memory. If the program cannot load the entire input file in one attempt, it will sort the contents of memory and write it to a temporary disk file. It will then clear the memory, and read again. Once all the input has been read, the program will then merge the temporary files into an output file. NJSORT will look for the environment variables NJTEMP, TEMP, and TMP to see if a path or drive for the temporary files was specified. The first variable found will be used for the temporary file area. Specifying no variable will result in the temporary files being stored on the current drive in the current directory. Using a large RAM disk, such as NJRAMD, for the temporary files will greatly increase the speed with which the merge takes place. The area specified for the temporary area, however, must be large enough to hold the entire file. This "sort and merge" method allows NJSORT to sort files that are much larger than memory. However, in the worst case, NJSORT will need twice the lenght of the file available as free space to sort the file. If, for example, you have a 100000 character file to sort, you must have at least 200000 bytes of free space on the diskette you wish to sort on. If you specify an alternate temporary directory, NJSORT only needs enough space to store the output file. The disk will contain the 100000 byte file and the 100000 byte output file, and the TEMP directory will contain the 100000 bytes of temporary files. On my 640k system, with 580k after DOS and all TSRs are loaded, NJSORT can typically sort files between 450 and 500 kilobytes in length without having to use temporary disk files. The complete sourcecode to the program is included in NJSORT.C and COMPARES.ASM. The makefile used to build the program is called NJSORT. I used BREIF to edit all the files here. Since I am a fool for good formatting, I set BRIEF's tab stops at every three characters for .C files and at the This program is a work of Shareware. I am requesting a $10 registration if you like the program. If you do not like, or do not use, the program, please pass it on to a friend or another BBS. Currently, I have not found any bugs in NJSORT. I have run billions of bytes of data through it in constructing and testing the program. I have not found any problems with even the largest files using many keys and fields. One note, however. Even if the input file contains an end of file marker, NJSORT will NOT write the marker to the output file. For this reason, the output file may be one byte shorter than the input file. Thank you very much! Mike "Nifty James" Blaszczak 35 Ginger Lane #229 East Hartford, Connecticut 06118 Version 1.10 Changes --- Version 1.10 implemented the /W# option to allow sorting of fixed-length fields. This option may be specified to cause NJSORT to treat the input file as a file of records that are the of the specified length. No terminating character will be looked for in the records; they will simply be read as blocks of bytes. This option does not work with the /I option to ignore whitespace. It also will not work with the /C option to fix case, or the /D option to blast duplicate lines. Of course, the /N and /M options are not allowed, either, as they support different reading methods. The sort key options may be used. They will specify the byte offsets into the records at which keys should be considered. /F0 is the first byte of the record, for example. If the file to be sorted contains incomplete records, NJSORT will not complete the sort. Besides swapping the records, no other action is taken upon the binary data. The new version contains a small change that allows more items to be sorted in memory. Previously, NJSORT would create a temporary file if more than 8000 items need to be sorted. Now, NJSORT will wait until there are 13000 items in memory before creating a temporary file. This improves efficiency if the items in memory are all rather short. Version 1.10 corrected some bugs that came about when sorting files larger than memory. There were a handful of other minor bugs corrected throughout the program. In Version 1.10, the COMPARES.ASM module was changed for the Microsoft Macro Assembler Version 5.10. This will allow compatibility for a possible later release of NJSORT which will use the newer Microsoft Languages to provide compatibility with NJSORT and versions of OS/2. Version 1.11 Changes --- A user in Hawaii provided most of the feedback that brought about this new version. A problem in NJSORT's merge caused records to be dropped in some larger-than-memory sorts. This problem has been corrected, and NJSORT should no longer lose information while sorting larger files. An additional option has also been added to NJSORT; /O#. This option will allow the user to have NJSORT ignore the first records of the file to be sorted. As an example, /O5 would cause NJSORT to read the first five records or lines from the input file and write them to the ouput file without changing their order. NJSORT underwent a few other changes to improve its speed. The program should prove to be slightly more efficient than the previous version. Previously, NJSORT would incorrectly report the number of records or lines sorted. This has been fixed in the new version. NJSORT Error Messages These are the error messages that NJSORT can generate, and the cause for each: NJSORT: Can't Sort a file with extension .BAK A file with the extension of .BAK was supplied to NJSORT as the filename to sort. Since NJSORT names the sorted output with the filename extension of .BAK, the program will not sort input files with the extension .BAK NJSORT: Not enough memory There was not enough memory to set up the basic housekeeping data areas that NJSORT needs. Generally, NSORT will require no more ten kilobytes of memory for its own internal data and buffer space. You should never see this error -- if you do, please make a note of the circumstances (computer, main memory, TSRs loaded, file size to be sorted, command line options, and DOS version) and send me the information. NJSORT: Can't write record number # in file "Filename" NJSORT: Can't write line number # in file "Filename" These errors can occur when NJSORT can not write to a file. If NJSORT runs out of space while writing a temporary file, or if the program runs out of space while writing the ouput file, this error will result. Try to create more free space on the device, or use another device that has more room. NJSORT: Record # was incompletely read, only # of # bytes In a Binary record sort, if NJSORT tries to read a record of the specified length and actually reads less information than that, this error will result. The most common cause of this error is specifying a record length that is not divisible by the size of the file to be sorted. For example, if the file is 1050 bytes long and a record length of 100 was specified, NJSORT would only find ten 100 byte records; the remaining 50 bytes would not constitute a full, sortable record. NJSORT: Input line # exceeds 2047 characters NJSORT cannot handle records longer than 2047 characters when doing an ASCII sort. The input file is simply too wide to sort. This error also comes about when NJSORT gets a binary file and wasn't given the /W parameter. NJSORT: there weren't enough input records to skip You told NJSORT to skip more records than were actually found in the input file. Lessen the number of records to skip. NJSORT: can't have both <something> and <something else> When parsing the options specified, NJSORT found two conflicting options. Some options are incompatible; for example, you can not specify both /W and /M. NJSORT: key offset greater than recwidth In a Binary Sort, NJSORT realized a record with was specified and one of the keys was given as having an offset greater than that record width. Check the parameters that you gave. NJSORT: must have at least one field with /M or /N The /M and /N options imply the use of sorting fields, and no field size or offset was specified. NJSORT: <key> was too big One of the specified key widths was larger than 2047, the maximum record size for NJSORT. NJSORT: Can't open <filename> for input The specified file was not found or was not available to NJSORT for read access. NJSORT: Can't open <filename> for output The requested or default output file was not valid or could not be created by NJSORT. NJSORT: Too many temporary files! Could not sort. NJSORT needed to use more than eighteen temporary files, and could not do so. This error should only occur when sorting files in the range of four to ten megabytes -- if it happens in less demanding circumstances, inform the author. NJSORT: Couldn't setup temporary buffer A problem occurred with NJSORT while trying to manipulate a temporary file. This error should rarely occur. If it happens twice, make a note of the environment and notify the author. NJSORT: Couldn't open file <filename> for temporary use There was a problem in accessing a temporary file. This should not occurr, unless the temporary file area ran out of space just as NJSORT was opening the file. Also, in a multiuser environment, if another program attempts to manipulate NJSORT's temporary file, this error may result.