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Full Discussion: Bash variable expansion
Top Forums Shell Programming and Scripting Bash variable expansion Post 302997736 by jcdole on Thursday 18th of May 2017 04:03:25 PM
Old 05-18-2017
Bash variable expansion

Hello.
The file /etc/fstab contains
Code:
UUID=957c3295-9944-1593-82e2-2b90dede4312 /                     ext4       noatime,discard,acl,user_xattr        1 1

I fill a variable
Code:
SOME_LINE=$( cat /etc/fstab | grep \/\..*ext4 | grep noatime,discard )

echo $SOME_LINE
Code:
UUID=957c3295-9944-1593-82e2-2b90dede4312 / ext4 noatime,discard,acl,user_xattr 1 1

echo ${SOME_LINE}
Code:
UUID=957c3295-9944-1593-82e2-2b90dede4312 / ext4 noatime,discard,acl,user_xattr 1 1

echo "$SOME_LINE"
Code:
UUID=957c3295-9944-1593-82e2-2b90dede4312 /                     ext4       noatime,discard,acl,user_xattr        1 1

I would like to know why The 3 outputs are not the same.

Thank you for helping.

Last edited by jcdole; 05-18-2017 at 06:51 PM..
 

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platform::shell(n)					       Tcl Bundled Packages						platform::shell(n)

__________________________________________________________________________________________________________________________________________________

NAME
platform::shell - System identification support code and utilities SYNOPSIS
package require platform::shell ?1.1.4? platform::shell::generic shell platform::shell::identify shell platform::shell::platform shell _________________________________________________________________ DESCRIPTION
The platform::shell package provides several utility commands useful for the identification of the architecture of a specific Tcl shell. This package allows the identification of the architecture of a specific Tcl shell different from the shell running the package. The only requirement is that the other shell (identified by its path), is actually executable on the current machine. While for most platform this means that the architecture of the interrogated shell is identical to the architecture of the running shell this is not generally true. A counter example are all platforms which have 32 and 64 bit variants and where a 64bit system is able to run 32bit code. For these running and interrogated shell may have different 32/64 bit settings and thus different identifiers. For applications like a code repository it is important to identify the architecture of the shell which will actually run the installed packages, versus the architecture of the shell running the repository software. COMMANDS
platform::shell::identify shell This command does the same identification as platform::identify, for the specified Tcl shell, in contrast to the running shell. platform::shell::generic shell This command does the same identification as platform::generic, for the specified Tcl shell, in contrast to the running shell. platform::shell::platform shell This command returns the contents of tcl_platform(platform) for the specified Tcl shell. KEYWORDS
operating system, cpu architecture, platform, architecture platform::shell 1.1.4 platform::shell(n)
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