[ILUG] ksh question

[Darragh Bailey]

On Thu, May 08, 2008 at 03:38:00PM +0200, Brian Foster wrote:
>   | Date: Thu, 8 May 2008 14:11:26 +0100
>   | From: "Braun Brelin" <bbrelin at gmail.com>
>   | Someone sent me the following lines in a Makefile:
>   | 
>   | XML_RULE = @echo " xml-rule $< xml2hpp.xsl $@" && \
>   | $(JAVA_BIN) -cp $(XT_DIR)/xp.jar:$(XT_DIR)/xt.jar \
>   | com.jclark.xsl.sax.Driver \
>   | $< $(CMKCMK)/xml2hpp.xsl $@
>   | 
>   | They wanted to know what the "$<" and "$@" symbols mean.
>   |[ ... ]
>   | Anyone else know what $< is in KSH?
> 
>  AFAICR, there is $< in ksh(1).
> 
>  ‘make’ has truely awful syntax, and the semantics
>  can be rather daunting at times as well.

"info make" and look at the quick reference is an easy way to checkup
what any of the syntax in make does.

keep in mind that $< resolves in fact to the "first" dependency of the
rule it is used under. That might not have been clear from the example
sent previously.

A clearer example would be

monday: tuesday wednesday
		@echo $< $@

'make monday' would print
tuesday monday

ignoring wednesday

-- 
Darragh

"Nothing is foolproof to a sufficiently talented fool."