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Full Discussion: What's wrong with this line: if ${TEST:?} ; then echo empty; fi
Top Forums UNIX for Dummies Questions & Answers What's wrong with this line: if ${TEST:?} ; then echo empty; fi Post 302169936 by zazzybob on Saturday 23rd of February 2008 05:14:55 AM
Old 02-23-2008
Code:
$ cat > foo.ksh
#!/bin/ksh
TEST=
FOO=${TEST:?empty}
$ chmod +x ./foo.ksh$ ./foo.ksh
./foo.ksh: line 3: TEST: empty
$ sed 's/^TEST=/TEST=something/' foo.ksh > foo2.ksh
$ chmod +x ./foo2.ksh
$ ./foo2.ksh
$

No need for the conditional structure, a simple variable assignment will do it.

Cheers,
ZB
 

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LEARN ABOUT LINUX

let

let(1)                                                             User Commands                                                            let(1)

NAME

       let - shell built-in function to evaluate one or more arithmetic expressions

SYNOPSIS

   ksh
       let arg...

DESCRIPTION

   ksh
       Each arg is a separate "arithmetic expression" to be evaluated.

EXIT STATUS

       The following exit values are returned:

       0        The value of the last expression is non-zero.

       1        The value of the last expression is zero.

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE         |      ATTRIBUTE VALUE        |
       +-----------------------------+-----------------------------+
       |Availability                 |SUNWcsu                      |
       +-----------------------------+-----------------------------+

SEE ALSO

       ksh(1), set(1), typeset(1), attributes(5)

SunOS 5.10                                                          15 Apr 1994                                                             let(1)
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