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Top Forums Shell Programming and Scripting Do something only that last iteration of loop Post 302770107 by Corona688 on Thursday 14th of February 2013 12:54:08 PM
Old 02-14-2013
Use -z for that. -z tests if a string is blank.

Code:
if [ ! -z "$2" ]
then
        echo "value $2"
else
        echo "2 is blank"
fi

And don't leave out the quotes. [ ! -z ] is a syntax error, [ ! -z "" ] is not.
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ECHO(1) 						    BSD General Commands Manual 						   ECHO(1)

NAME
echo -- write arguments to the standard output SYNOPSIS
echo [-n] [string ...] DESCRIPTION
The echo utility writes any specified operands, separated by single blank (' ') characters and followed by a newline (' ') character, to the standard output. The following option is available: -n Do not print the trailing newline character. This may also be achieved by appending 'c' to the end of the string, as is done by iBCS2 compatible systems. Note that this option as well as the effect of 'c' are implementation-defined in IEEE Std 1003.1-2001 (``POSIX.1'') as amended by Cor. 1-2002. Applications aiming for maximum portability are strongly encouraged to use printf(1) to sup- press the newline character. Some shells may provide a builtin echo command which is similar or identical to this utility. Most notably, the builtin echo in sh(1) does not accept the -n option. Consult the builtin(1) manual page. EXIT STATUS
The echo utility exits 0 on success, and >0 if an error occurs. SEE ALSO
builtin(1), csh(1), printf(1), sh(1) STANDARDS
The echo utility conforms to IEEE Std 1003.1-2001 (``POSIX.1'') as amended by Cor. 1-2002. BSD
April 12, 2003 BSD
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