Location: Saint Paul, MN USA / BSD, CentOS, Debian, OS X, Solaris
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Hi.
I ended up with a long script that compared the results of cut, 3 variations of sed, and the binary editor bbe. I did these on Linux and Solaris 10 (but bbe omitted on Solaris). I used cmp as the first test, and then diff for the detailed comparison. On Linux, GNU diff bails out quickly, simply saying that the binary files differ.
The sed variations that I used were:
Code:
sed 's/^..//' ...
sed 's/^.\{2\}//' ...
sed 's/^.{2}//' ...
I used the cut output as the standard. The bbe output compared successfully.
Observations:
1) mixed-mode files are not best-practice
2) cut knows about bytes, and appears to use its byte "knowledge" as its character knowledge
3) sed is advertised as:
Code:
sed - stream editor for filtering and transforming text
not necessarily collections of arbitrary bytes in mixed-mode files
4) At the center where I worked, we said that we could make processes (almost) as fast as you desired as long as you didn't care about the results. If you get good results in a reasonable time from a particular process, then use it. You may end up wasting more time trying to find the fastest method than if you just let the original process run. This is a kind of case of premature optimization, along with the notion that people time is the most expensive (in most cases).
5) I did not time bbe, but it might be as fast as sed -- it is:
Code:
bbe is a sed-like editor for binary files. It performs binary transfor-
mations on the blocks of input stream.
I can post the script and results, however, as I said, they are lengthy. As usual, it is possible that I have incorporated an error of some kind, but in general I agree with the OP ... cheers, drl
A quick peek at sample.conf shows that the first byte in the lines is a null byte. It's a safe bet that what you are seeing is a sideeffect of c string functions interpreting a null byte as end of string.
For experimentation's sake, does the discrepancy persist if you substitute a 001 byte for the 000 bytes?
Code:
tr \\000 \\001 < withnull > withoutnull
If it does not, mystery solved. If it does, weird. Could that sed implementation be filtering out control characters?
Hi I'm having a problem with a sed command that I thought I was using correctly but apparently that's not the case.
I was hoping someone here could point out what it is I am doing wrong?
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Hi, all.
Here's the problem:
sed '/FOO/,/BAR/p'
That should print anything between FOO and BAR, right?
Well, let's say I have file.txt that contains just one line "how are you today?".
Then I run something like the above and get:
$ sed '/how/,/today/p' file.txt
how are you... (9 Replies)
HI all
I have written a ksh to execute PL/sql procedure and generate the log file. The script is working fine to the extent of calling the taking input, executing PL/SQL procedure.
On one server the log file is getting generated properly. i,e it shows the DBMS output . The log file size was... (9 Replies)
Hi,
We have few hundered scripts using cut command in thousands of lines. On HP-UX shell script developer used echo "ABCEFG" | cut -c -1-3 to cut first three character of the string. We recently moved to Linux and this command throws error. I think this might be due to different version of... (3 Replies)
Here is my test script:
#!/bin/sh
result=`jobs`
echo "
Jobs:
"$result
result=`ls`
echo "
LS
"$result
Here is the output:
Jobs:
LS
0 1 2 3 4 5 6 7 gcd initialize.sh #inter_round_clean.sh# inter_round_clean.sh inter_round_clean.sh~ look parallel_first_run.sh... (3 Replies)
Guys i have strange behaviour with command output being saved in a variable instead of a tmp file.
1. I suck command output into a variable
Sample command output
# cleanstats
DRIVE INFO:
----------
Drv Type Mount Time Frequency Last Cleaned Comment
*** ****... (1 Reply)
All,
I have a script that runs on 2 servers and there seems to be something wrong. It's producing different results on the 2 servers.
Here is the script on server1 which is behaving correctly but on 2 behaving differently.
2nd server:
I couldn't make out whats the error is?... (5 Replies)
Hi,
I wrote a script to stop a process,truncate its log files and re-start the process...
We are using Progress Software in Unix ( Sun Sparc)
When ever I start this progress program , it should kick off a C pgm in the background..
The script work perfectly fine when I run it from command... (4 Replies)
I posted this in Shell scripting... maybe I'll try it in this forum..
*****************
I wrote a script to stop a process,truncate its log files and re-start the process...
We are using Progress Software in Unix ( Sun Sparc)
When ever I start this progress program , it should kick off a... (1 Reply)
