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1530
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location United States
age 53
visits member for 5 years, 1 month
seen Aug 27 at 17:15
Long-time Informix user and developer, experienced in C and Unix (many variants). Email: jonathan.leffler@gmail.com

May
21
answered ~/.profile does not run on startup
May
14
comment Linux Directory Access Problem: Permission Denied “”“In Root”“”
That's an unusual permission string; the dashes should be missing. Also, NEVER have public write permission on the root directory.
May
13
comment How to get relative path from two absolute paths in linux shell?
Thank you - saves me looking up the discussion.
May
6
comment How to compare file timestamps in bash?
The test mechanism is very complex compared with the built in mechanism for comparing time stamps.
May
6
comment How to compare file timestamps in bash?
Your code needs spaces around the square brackets.
May
6
answered How to compare file timestamps in bash?
May
6
comment CPU I/O communication
@b-gen-jack-o-neill: for an IN or OUT instruction, the memory would (normally) ignore the request because the I/O pin is asserted. With memory mapped I/O, there is no RAM at the address - the I/O device is mapped there. So, the net result is "no, what is written goes to the I/O device". If someone misdesigned the memory system, I suppose you might have memory paying attention to the I/O request, but chaos will ensue -- does the I/O device or the memory win on an IN instruction where the memory tries to provide an answer as well as the I/O device. It won't work, and hence you won't see it.
May
2
revised CPU I/O communication
Fix trivial typo
May
1
answered CPU I/O communication
Apr
29
answered How can I still see the 'man' text after I quit man?
Apr
26
answered How are PID's generated?
Apr
25
answered rm -rf not erasing directory
Apr
18
revised xargs command works on ubuntu, but not mac
Tighten up the characterizatin of the first grep command
Apr
18
comment xargs command works on ubuntu, but not mac
@Corey: Is '${today}' something like '17/04/2010'? If so, you need to change the 's///' notation to 's%%%' instead - using the % or another character that does not appear in either pattern to separate the parts of the substitute operation. I'm not sure how you get 'sed' thinking there's a change command in the mix. You're right; xargs fixes things so that the executed command has /dev/null for its input, and the file names to be operated on as arguments. What's wrong with the Mac term that isn't fixed by switching from tcsh to a sane shell? And which do you prefer on the other system?
Apr
18
comment Need a Linux command that takes much time
That's a hard way of doing 'sleep 10'?
Apr
17
answered xargs command works on ubuntu, but not mac
Apr
12
revised Would running sudo rm -rf / in OS X wipe out any attached time machine backups?
Fix trivial typo
Apr
11
comment Which file systems support newlines in file names?
When Steve Bourne was testing his shell, he had a directory with 254 single-character file names in it - and it wrought havoc on programs that were not expecting such characters in file names.
Apr
11
answered Would running sudo rm -rf / in OS X wipe out any attached time machine backups?
Apr
8
answered find . -exec grep -l 'string' {} \; -print 2>/dev/null