compression - Word Length as defined in the .ZIP format specification -

-

so i've been reading through pkware's specification of .zip file format , have noticed in several places give block sizes in terms of words (the processor word, not dictionary word :-) ).

now, way understand it, byte size of word specific processor family. if file zipped on i386 , unzipped on x64-86, 2 architectures have different definitions of word (4 bytes vs. 8 bytes) , therefore interpret block data differently.

am missing here? or folks @ pkware assume 1 word = 4 bytes? seems option me - i've checked zip files hex editor , 4-byte definition fit, i'd confirmation because not have whole bunch of different processors test :)

thanks in advance, , sorry if question exists - did try searching it's little difficult because word "word" ambiguous (see mean?)

where specification says "word" stored block in deflate format, means 2 bytes (in lsb order).

for zip decryption (where said encryption should not used since it's weak), again word means 2 bytes.

when talks general purpose flag word under imploding, again means 2 bytes.


Comments

Post a Comment

Popular posts from this blog

c# - SVN Error : "svnadmin: E205000: Too many arguments" -

-
i trying reposotries using c# code process svncommand = null; var psi = new processstartinfo("svnadmin"); psi.redirectstandardoutput = true; psi.redirectstandarderror = true; psi.useshellexecute = false; psi.arguments= @"dump c:\repositories\myrepo > c:\temp\myrepodumpfile.dump"; using (svncommand = process.start(psi)) { var myoutput = svncommand.standardoutput; var myerror = svncommand.standarderror; debug.write("output :" + environment.newline + environment.newline + myoutput.readtoend() + environment.newline + "error :" + environment.newline + environment.newline + myerror.readtoend()); svncommand.close(); } when use dump command commandline svnadmin dump c:\repositories\myrepo > c:\temp\myrepodumpfile.dump it works fine when try ...
Read more

c++ - Using OpenSSL in a multi-threaded application -

-
i have been writing soap client application in c++ on ubuntu using openssl https transport , pthreads threading. have number of threads - 1 central data acquisition thread periodically gets worker threads make soap requests via shared mutex protected queues. reading documentation openssl found is openssl thread-safe? in openssl faq describes mechanisms required ensure thread safety when using openssl. implemented , works fine. the reason question conceptual difficulty really. thinking implementing same functionality application has already, instead of using threads, create 2 seperate applications : 1 worker thread (of multiple copies running) , main data acquisition thread. use tcp sockets communicate between 2 rather mutex protected queues. may bad idea not important - confusing me would have implement same functions required ensure openssl thread safety in second approach or not? my guess not have , treated independent (indeed surely must many applications use openssl) re...
Read more

All overlapping substrings matching a java regex -

-
is there api method returns (possibly overlapping) substrings match regular expression? for example, have text string: string t = 04/31 412-555-1235; , , have pattern: pattern p = new pattern("\\d\\d+"); matches strings of 2 or more characters. the matches are: 04, 31, 412, 555, 1235. how overlapping matches? i want code return: 04, 31, 41, 412, 12, 55, 555, 55, 12, 123, 1235, 23, 235, 35. theoretically should possible -- there obvious o(n^2) algorithm enumerates , checks substrings against pattern. edit rather enumerating substrings, safer use region(int start, int end) method in matcher . checking pattern against separate, extracted substring might change result of match (e.g. if there non-capturing group or word boundary check @ start/end of pattern). edit 2 actually, it's unclear whether region() expect zero-width matches. specification vague, , experiments yield disappointing results. for example: string line = "xx90xx"; strin...
Read more