Shell

When do I need `expr ......` and when not? $(($aaa - $bbb))simplyfiable?
2008-06-15, 06:48(+00), Wolfgang Meister: As I learned it is not always necessary to use `expr ....` (with backticks) to calculate mathematical expressions. When I do for example the following firstsec=345 secondsec=723 diffsec=$((secondsec - firstsec)) echo diff=$diffsec then it works altho... 19 Jun 2008 01:20

When do I need `expr ......` and when not? $(($aaa - $bbb)) simplyfiable?
As I learned it is not always necessary to use `expr ....` (with backticks) to calculate mathematical expressions. When I do for example the following firstsec=345 secondsec=723 diffsec=$((secondsec - firstsec)) echo diff=$diffsec then it works although I did not used "expr" for calculate the difference. ... 12 Jul 2008 15:37

Olympialaisia ter�v�n�
*Koska olemme varsin pitk��n tienneet, ett� MY�S Marssissa on ollut ja on yh� valtaisat vesivarannot, siihen liittyv�t mekaniikat tietysti meit� my�s jatkossa kiinnostavat. T�ss� aiheesta lis��: Marsin pinnalla joskus lainehtinut vesi oli niin pikisuolaista, ett� ainakaan Maan pinnalla esiintyv�t el�m�nmuodot eiv... 19 Jun 2008 01:20

zsh shell string question
In article <c820d5c3-6875-4ca0-825a-c93b96481b0f(a)z16g2000prn.googlegroups.com>, Chad <cdalten(a)gmail.com> wrote: On Jun 13, 8:12�pm, Barry Margolin <bar...(a)alum.mit.edu> wrote: In article <91c0237b-9c76-47ca-ba83-0d7d391fd...(a)s21g2000prm.googlegroups.com>, �Chad <cdal...@... 19 Jun 2008 01:20

Execute second command only if first fails/succeeds?
2008-06-14, 08:28(+00), Matthew Lincoln: I am not sure about on how to specify that a second command should only be execute in case that the first commnd fails/succeeds. When I enter: cmd1 | gzip -f ... && cmd2 Is then cmd2 executed only if cmd1 is finished successfully or if gzip is finished su... 19 Jun 2008 01:20

Get the md5sum of every 64MB block in a large file using bash.
Hello, can someone please help. I have an 8GB file and need the md5sum of every 64MB block in the file. I'm looking for some ideas on how to write a script to do this using bash - not interested in perl or other language solutions. The size of my disk is 10GB with a smallish linux system and 256MB free disk... 7 May 2008 15:04

Gawk match() and numbers in scientific notation
On 5/7/2008 11:04 AM, pk wrote: On Wednesday 7 May 2008 17:37, Ed Morton wrote: these locales, `[a-dx-z]' is typically not equivalent to `[abcdxyz]'; instead it might be equivalent to `[aBbCcDdxXyYz]', for example. Is there a way to explicitly print out that information (or, better, t... 7 May 2008 15:04

scp script
I have a script that is set up using ID: infa123 The script will scp files from one machine to another and only infa123 can write to the directories. The public key is set up so that the password is not prompted during the scp. I need to have a user execute this script but they would ha... 7 May 2008 13:25

How to to define the size of a file in scripting
Hi everyone, I am writing a small script for log files whenever the size of a file exceeds it has to compress the file or split it into to file i want to know how to to define the size of file in scripting i am tring in the following way logtest=/var/log/testmessages 4 logsize="ls -lh /var/log/testmessa... 7 May 2008 14:14

How to exclude MULTIPLE directories in a rsync command ?
As I learned from the man page of rsync I can exclude a certain directory (trees) by using the --exclude option like in rsync .... --exclude=/proc .... But how do I exclude multiple directory (trees) at once in such a rsync command? The following does not work: rsync .... --exclude=/proc||/var||/dummy .... ... 7 May 2008 05:05