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Full Discussion: Bash variable expansion
Top Forums Shell Programming and Scripting Bash variable expansion Post 302997738 by Don Cragun on Thursday 18th of May 2017 04:15:26 PM
Old 05-18-2017
Without quotes, the words in the expansion of $MY_TOKEN are passed to echo as separate arguments by the shell. The echo utility then prints each of its arguments separated by a <space> character and adds a <newline> at the end to produce a line of output.

With quotes, the shell does not perform field splitting and the quoted string is passed to echo as a single argument. And, again, the echo utility prints its argument and adds a <newline> at the end to produce a line of output.
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line(1) 						      General Commands Manual							   line(1)

NAME
line - Reads one line from standard input SYNOPSIS
line STANDARDS
Interfaces documented on this reference page conform to industry standards as follows: line: XCU5.0 Refer to the standards(5) reference page for more information about industry standards and associated tags. OPTIONS
None DESCRIPTION
The line command copies one line, up to and including a newline, from standard input and writes it to standard output. Use this command within a shell command file to read from your terminal. The line command always writes at least a newline character. NOTES
The line utility has no internationalization features and is marked LEGACY in XCU Issue 5. Use the read utility instead. EXIT STATUS
Success. End-of-File. EXAMPLES
To read a line from the keyboard and append it to a file, enter: echo 'Enter comments for the log:' echo ': c' line >>log This shell procedure displays the message: Enter comments for the log: It then reads a line of text from the keyboard and adds it to the end of the file log. The echo ': c' command displays a : (colon) prompt. See the echo command for information about the c escape sequence. SEE ALSO
Commands: echo(1), ksh(1), read(1), Bourne shell sh(1b), POSIX shell sh(1p) Functions: read(2) Standards: standards(5) line(1)
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