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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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SHTOOL-ECHO.TMP(1)					      GNU Portable Shell Tool						SHTOOL-ECHO.TMP(1)

NAME
shtool-echo - GNU shtool echo(1) extensional command SYNOPSIS
shtool echo [-n|--newline] [-e|--expand] string DESCRIPTION
shtool echo is an echo(1) style command which prints string to stdout and optionally provides special expansion constructs (terminal bold mode, environment details, date, etc) and newline control. The trick of this command is that it provides a portable -n option and hides the gory details needed to find out the environment details under option -e. OPTIONS
The following command line options are available. -n, --newline By default, output is written to stdout followed by a "newline" (ASCII character 0x0a). If option -n is used, this newline character is omitted. -e, --expand If option -e is used, string can contain special "%x" constructs which are expanded before the output is written. Currently the following constructs are recognized: %B switch terminal mode to bold display mode. %b switch terminal mode back to normal display mode. %u the current user name. %U the current user id (numerical). %g the current group name. %G the current group id (numerical). %h the current hostname (without any domain extension). %d the current domain name. %D the current day of the month. %M the current month (numerical). %m the current month name. %Y the current year. EXAMPLE
# shell script shtool echo -n -e "Enter your name [%B%u%b]: "; read name shtool echo -e "Your Email address might be %u@%h%d" shtool echo -e "The current date is %D-%m-%Y" HISTORY
The GNU shtool echo command was originally written by Ralf S. Engelschall <rse@engelschall.com> in 1998 for Website META Language (WML) under the name buildinfo. It was later taken over into GNU shtool. SEE ALSO
shtool(1), echo(1). 18-Jul-2008 shtool 2.0.8 SHTOOL-ECHO.TMP(1)
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