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Are you saying it echoed &quot;12345&quot;? &nbsp;It echoed 5 digits?
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Are you saying it echoed "12345"?  It echoed 5 digits?

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Thanks for your help. &nbsp;Appreciated
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I think due change of interface, I had awarded points but it did not go through. &nbsp;Please open it again so that I can award points. &nbsp;Thanks.
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I think due change of interface, I had awarded points but it did not go through.  Please open it again so that I can award points.  Thanks.

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The result of the following match is successful. Why?<br />
&nbsp;x=12345 ; [[ $x =~ ^[0-9]{3} ]] &amp;&amp;&nbsp;echo 3 digits<br />
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I thought I wanted only 3 digits. &nbsp;So to me it should have failed. &nbsp;I was only expecting it to work for x=123.<br />
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Please explain. &nbsp;Also if I want to match only 3 digits, what would be the regular expression?
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The result of the following match is successful. Why?
 x=12345 ; [[ $x =~ ^[0-9]{3} ]] && echo 3 digits

I thought I wanted only 3 digits.  So to me it should have failed.  I was only expecting it to work for x=123.

Please explain.  Also if I want to match only 3 digits, what would be the regular expression?

Bash Regular expression

Linux is a UNIX-like open source operating system with hundreds of distinct distributions, including: Fedora, openSUSE, Ubuntu, Debian, Slackware, Gentoo, CentOS, and Arch Linux. Linux is generally associated with web and database servers, but has become popular in many niche industries and applications.

Linux

The term 'shell' refers to a general class of text-based command interpreters most often associated with the UNIX and Linux operating systems. Popular shells include Bourne, Debian Almquist (dash), Korn (ksh), Bourne Again (bash) and the C shell family (csh). Some view the DOS 'cmd' prompt as a minimal shell of sorts. It is also possible to install Cygwin on Windows and emulate a full Unix environment with complete shell capabilities. Terminal emulators, such as xterm, GNOME Terminal and OS X Terminal, can be used to access shell.

Shell Scripting

A scripting language is a programming language that supports scripts, programs written for a special run-time environment that automate the execution of tasks that could alternatively be executed one-by-one by a human operator. Scripting languages are often interpreted (rather than compiled). Primitives are usually the elementary tasks or API calls, and the language allows them to be combined into more complex programs. Environments that can be automated through scripting include software applications, web pages within a web browser, the shells of operating systems (OS), embedded systems, as well as numerous games. A scripting language can be viewed as a domain-specific language for a particular environment; in the case of scripting an application, this is also known as an extension language.