Re: When scripting, which is better?

> Hi all,
>
> Reading through the script files again, there seems to be several
> different methods of doing the same thing :
>
> i.e. if [ -x "$self_path/postmaster" ] && [ -x "$self_path/psql" ];
> then

The above semicolon is useless. Actually, I have never see this. The
normal way is:

if [ -x "$self_path/postmaster" -a -x "$self_path/psql" ]

>
> or
>
> if [[ -x "$self_path/postmaster" && -x "$self_path/psql" ]]; then

I usually do:

if [ ... ]
then

Pretty simple.

>
>
>
>
> if [ x"$foo" = x"" ]; then
>
> or
>
> if [ "$op" = "" ]; then

This is done if you think $op may have a leading dash.

>
> or
>
> if [ "$foo" ]; then
>

This tests whether "$foo" is not equal to "".

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