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From: "Robert P. J. Day" <rpjday@crashcourse.ca>
To: OE Core mailing list <openembedded-core@lists.openembedded.org>
Subject: what is the value of 'BBPATH ?= ""' in layer.conf?
Date: Sun, 22 Nov 2015 04:10:51 -0500 (EST)	[thread overview]
Message-ID: <alpine.LFD.2.20.1511220407380.13727@localhost> (raw)


  perusing some wind river layers, and in the layer.conf file here:

https://github.com/WindRiver-OpenSourceLabs/wr-kernel/blob/LB21_7.0_RCPL0002/conf/layer.conf

i see the opening snippet:

  BBPATH ?= ""
  # We have a conf and classes directory, add to BBPATH
  BBPATH := "${LAYERDIR}:${BBPATH}"

what is the purpose of that initial assignment

  BBPATH ?= ""

if that variable has no value, won't it just expand to the empty
string so that the eventual effect is the same? or is there something
more subtle happening here?

rday

-- 

========================================================================
Robert P. J. Day                                 Ottawa, Ontario, CANADA
                        http://crashcourse.ca

Twitter:                                       http://twitter.com/rpjday
LinkedIn:                               http://ca.linkedin.com/in/rpjday
========================================================================



             reply	other threads:[~2015-11-22  9:10 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-11-22  9:10 Robert P. J. Day [this message]
2015-11-22  9:17 ` what is the value of 'BBPATH ?= ""' in layer.conf? Robert Yang
2015-11-22  9:29   ` Robert P. J. Day
2015-11-22  9:38     ` Robert Yang
2015-11-23 14:16 ` Mark Hatle

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