| HTTP Content Coding Token | gzip | deflate | compress |
|---|---|---|---|
| An encoding format produced by the file compression program "gzip" (GNU zip) | The "zlib" format as described in RFC 1950. | The encoding format produced by the common UNIX file compression program "compress". | |
| Data Format | GZIP file format | ZLIB Compressed Data Format | The compress program's file format |
| Compression Method | Deflate compression method | LZW | |
| Deflate consists of LZ77 and Huffman coding | |||
Compress doesn't seem to be supported by popular current browsers, possibly due to its past with patents.
Deflate isn't done correctly all the time. Some servers would send the deflate data format instead of the zlib data format and at least some versions of Internet Explorer expect deflate data format instead of zlib data format.
I wanted to ensure that my switch statement in my implementation of IInternetSecurityManager::ProcessURLAction had a case for every possible documented URLACTION. I wrote the following short command line sequence to see the list of all URLACTIONs in the SDK header file not found in my source file:
grep URLACTION urlmon.idl | sed 's/.*\(URLACTION[a-zA-Z0-9_]*\).*/\1/g;' | sort | uniq > allURLACTIONs.txt
grep URLACTION MySecurityManager.cpp | sed 's/.*\(URLACTION[a-zA-Z0-9_]*\).*/\1/g;' | sort | uniq > myURLACTIONs.txt
comm -23 allURLACTIONs.txt myURLACTIONs.txtBut in my effort to learn and use PowerShell I found the following similar command line:
diff
(more urlmon.idl | %{ if ($_ -cmatch "URLACTION[a-zA-Z0-9_]*") { $matches[0] } } | sort -uniq)
(more MySecurityManager.cpp | %{ if ($_ -cmatch "URLACTION[a-zA-Z0-9_]*") { $matches[0] } } | sort -uniq)
which command is a rather literal port and requires you to enter the entire name of the command for which you're looking. That is 'which which' won't find itself but
'which which.exe' will. This makes this almost useless for me so I thought to write my own as a batch file. I had learned about a few goodies available in cmd.exe that I thought would
make this an easy task. It turned out to be more difficult than I thought.for /F "usebackq tokens=*" %%a in ( `"echo %PATH:;=& echo %"` ) do (
for /F "usebackq tokens=*" %%b in ( `"echo %PATHEXT:;=& echo %"` ) do (
if exist "%%a"\%1%%b (
for %%c in ( "%%a"\%1%%b ) do (
echo %%~fc
)
)
)
)PATH and PATHEXT hold the list of paths to search through to find commands, and the extensions of files that should be run as
commands respectively. The 'for /F "usebackq tokens=*" %%a in (...) do (...)' runs the 'do' portion with %%a sequentially taking on the value of every line in
the 'in' portion. That's nice, but PATH and PATHEXT don't have their elements on different lines and I don't know of a way to escape a newline character to
appear in a batch file. In order to get the PATH and PATHEXT's elements onto different lines I used the %ENV:a=b% syntax which replaces occurrences of a with b
in the value of ENV. I replaced the ';' delimiter with the text '& echo ' which means %PATHEXT:;=& echo% evaluates to something like "echo
.COM& echo .EXE& echo .BAT& ...". I have to put the whole expression in double quotes in order to escape the '&' for appearing in the batch file. The usebackq and
the backwards quotes means that the backquoted string should be replaced with the output of the execution of its content. So in that fashion I'm able to get each element of the env. variable onto new
lines. The rest is pretty straight forward.C:\Users\davris>which.cmd *hi*
C:\Windows\System32\GRAPHICS.COM
C:\Windows\System32\SearchIndexer.exe
D:\bin\which.exe
D:\bin\which.cmd
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