Sponsored Content
Full Discussion: Unfamiliar array syntax
Top Forums Shell Programming and Scripting Unfamiliar array syntax Post 302453887 by Scrutinizer on Thursday 16th of September 2010 05:07:34 PM
Old 09-16-2010
This is construction that is used if a shell in question does not know arrays. The way it is used in the script that you were handed, is a bit cumbersome. Instead of
Code:
backup_host=`eval echo \\$collect${N}_backup_host`

this could be used:
Code:
eval backup_host=\$collect${N}_backup_host

eval works like this: first everything after eval is passed as parameter to eval. The shell processes the variable ${N}. The first $ is escaped ( \$ ), so that it is not treated as a special character. So after processing the command eval gets the following string (suppose N=1):
Code:
backup_host=$collect1_backup_host

end then executes this. As a result you would get:
Code:
$ N=1
$ eval backup_host=\$collect${N}_backup_host
$ echo $backup_host
alt-host.xxx.net


Last edited by Scrutinizer; 09-16-2010 at 06:32 PM..
 

9 More Discussions You Might Find Interesting

1. UNIX for Advanced & Expert Users

unfamiliar errors

I was checking my error logs today and ran into some errors I have not seen before maybe somebody has run into these before? /etc/cron.quarter-hourly/owusers.sh: Set effective gid to mail(12) failed! /usr/local/mailwatch/check_sendmail_relay.sh: line 8: thanks (1 Reply)
Discussion started by: mcraul
1 Replies

2. Programming

Creating an array to hold posix thread ids: Only dynamic array works

I am facing a strange error while creating posix threads: Given below are two snippets of code, the first one works whereas the second one gives a garbage value in the output. Snippet 1 This works: -------------- int *threadids; threadids = (int *) malloc (num_threads * sizeof(int)); ... (4 Replies)
Discussion started by: kmehta
4 Replies

3. Shell Programming and Scripting

PHP: Search Multi-Dimensional(nested) array and export values of currenly worked on array.

Hi All, I'm writing a nagios check that will see if our ldap servers are in sync... I got the status data into a nested array, I would like to search key of each array and if "OK" is NOT present, echo other key=>values in the current array to a variable so...eg...let take the single array... (1 Reply)
Discussion started by: zeekblack
1 Replies

4. Shell Programming and Scripting

PERL : Read an array and write to another array with intial string pattern checks

I have an array and two variables as below, I need to check if $datevar is present in $filename. If so, i need to replace $filename with the values in the array. I need the output inside an ARRAY How can this be done. Any help will be appreciated. Thanks in advance. (2 Replies)
Discussion started by: irudayaraj
2 Replies

5. Shell Programming and Scripting

Help with awk array syntax & counting script

..... (3 Replies)
Discussion started by: elbee11
3 Replies

6. UNIX for Dummies Questions & Answers

awk construct unfamiliar to me

Please help me out: I've seen this construct awk '{...}1'several times, like in scrutinizer's today's post awk '{for(i=2;i<=NF;i++)if($i==$1)$i=RS $i}1' infilebut I can't find (manuals, man pages, internet FAQs,...) an explanation of what it does resp. stands for. Any hint is appreciated! (5 Replies)
Discussion started by: RudiC
5 Replies

7. UNIX for Dummies Questions & Answers

awk: syntax for "if (array doesn't contain a particular index)"

Hi! Let's say I would like to convert "1", "2", "3" to "a", "b", "c" respectively. But if a record contains other number then return "X". input: 1 2 3 4 output: a b c X What is the syntax for: if(array doesn't contain a particular index){ then print the value "X" instead} (12 Replies)
Discussion started by: beca123456
12 Replies

8. Shell Programming and Scripting

Bash 3.2 - Array / Regex - IF 3rd member in array ends in 5 digits then do somthing...

Trying to do some control flow parsing based on the index postion of an array member. Here is the pseudo code I am trying to write in (preferably in pure bash) where possible. I am thinking regex with do the trick, but need a little help. pesudo code if == ENDSINFIVEINTS ]]; then do... (4 Replies)
Discussion started by: briandanielz
4 Replies

9. Shell Programming and Scripting

Bash arrays: rebin/interpolate smaller array to large array

hello, i need a bit of help on how to do this effectively in bash without a lot of extra looping or massive switch/case i have a long array of M elements and a short array of N elements, so M > N always. M is not a multiple of N. for case 1, I want to stretch N to fit M arrayHuge H = (... (2 Replies)
Discussion started by: f77hack
2 Replies
Locale::Codes::LangFam(3)				User Contributed Perl Documentation				 Locale::Codes::LangFam(3)

NAME
Locale::Codes::LangFam - standard codes for language extension identification SYNOPSIS
use Locale::Codes::LangFam; $lext = code2langfam('apa'); # $lext gets 'Apache languages' $code = langfam2code('Apache languages'); # $code gets 'apa' @codes = all_langfam_codes(); @names = all_langfam_names(); DESCRIPTION
The "Locale::Codes::LangFam" module provides access to standard codes used for identifying language families, such as those as defined in ISO 639-5. Most of the routines take an optional additional argument which specifies the code set to use. If not specified, the default ISO 639-5 language family codes will be used. SUPPORTED CODE SETS
There are several different code sets you can use for identifying language families. A code set may be specified using either a name, or a constant that is automatically exported by this module. For example, the two are equivalent: $lext = code2langfam('apa','alpha'); $lext = code2langfam('apa',LOCALE_LANGFAM_ALPHA); The codesets currently supported are: alpha This is the set of three-letter (lowercase) codes from ISO 639-5 such as 'apa' for Apache languages. This is the default code set. ROUTINES
code2langfam ( CODE [,CODESET] ) langfam2code ( NAME [,CODESET] ) langfam_code2code ( CODE ,CODESET ,CODESET2 ) all_langfam_codes ( [CODESET] ) all_langfam_names ( [CODESET] ) Locale::Codes::LangFam::rename_langfam ( CODE ,NEW_NAME [,CODESET] ) Locale::Codes::LangFam::add_langfam ( CODE ,NAME [,CODESET] ) Locale::Codes::LangFam::delete_langfam ( CODE [,CODESET] ) Locale::Codes::LangFam::add_langfam_alias ( NAME ,NEW_NAME ) Locale::Codes::LangFam::delete_langfam_alias ( NAME ) Locale::Codes::LangFam::rename_langfam_code ( CODE ,NEW_CODE [,CODESET] ) Locale::Codes::LangFam::add_langfam_code_alias ( CODE ,NEW_CODE [,CODESET] ) Locale::Codes::LangFam::delete_langfam_code_alias ( CODE [,CODESET] ) These routines are all documented in the Locale::Codes::API man page. SEE ALSO
Locale::Codes The Locale-Codes distribution. Locale::Codes::API The list of functions supported by this module. http://www.loc.gov/standards/iso639-5/id.php ISO 639-5 . AUTHOR
See Locale::Codes for full author history. Currently maintained by Sullivan Beck (sbeck@cpan.org). COPYRIGHT
Copyright (c) 2011-2013 Sullivan Beck This module is free software; you can redistribute it and/or modify it under the same terms as Perl itself. perl v5.16.3 2013-02-27 Locale::Codes::LangFam(3)
All times are GMT -4. The time now is 04:14 PM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy