Hi Rob Yes, I got your post. But after all the time I have spent with gcc, with all the options, I am mostly happy with just -wall. Yes, there is a distinction with #include saying 'these are system directories' vs 'these are personal or project directories'. But the defaults are fine for me. And I prefer to use unique include file names, supporting the KISS principle. Cheers Rick On March 31, 2016 12:00:02 PM EDT, linux-request [ at ] lists [ dot ] oclug [ dot ] on [ dot ] ca wrote: >Send Linux mailing list submissions to > linux [ at ] lists [ dot ] oclug [ dot ] on [ dot ] ca > >To subscribe or unsubscribe via the World Wide Web, visit > http://oclug.on.ca/mailman/listinfo/linux >or, via email, send a message with subject or body 'help' to > linux-request [ at ] lists [ dot ] oclug [ dot ] on [ dot ] ca > >You can reach the person managing the list at > linux-owner [ at ] lists [ dot ] oclug [ dot ] on [ dot ] ca > >When replying, please edit your Subject line so it is more specific >than "Re: Contents of Linux digest..." > > >Today's Topics: > > 1. still confused about the use of (now obsolete) "-I-" option > of gcc (Robert P. J. Day) > > >---------------------------------------------------------------------- > >Message: 1 >Date: Thu, 31 Mar 2016 07:38:17 -0400 (EDT) >From: "Robert P. J. Day" <rpjday [ at ] crashcourse [ dot ] ca> >To: Ottawa Linux Users Group <linux [ at ] lists [ dot ] oclug [ dot ] on [ dot ] ca> >Subject: [OCLUG-Tech] still confused about the use of (now obsolete) > "-I-" option of gcc >Message-ID: <alpine.LFD.2.20.1603310730040.3798@localhost.localdomain> >Content-Type: text/plain; charset=US-ASCII > > > i'm still trying to understand the *precise* mechanics of what >happens when one uses "-I-" to mangle the header file search path with >gcc. from the man page, it *seems* straight forward: > >-I- > >"Split the include path. Any directories specified with -I options >before -I- are searched only for headers requested with "#include >"file""; they are not searched for "#include <file>". If additional >directories are specified with -I options after the -I-, those >directories are searched for all #include directives. > >"In addition, -I- inhibits the use of the directory of the current >file directory as the first search directory for "#include "file"". >This option has been deprecated." > >but here's the part i'm still unclear on. > > as i understand it, the primary purpose of this option is to allow >the overriding of header files specified with quotes. normally, of >course, if you have: > > #include "rday.h" > >the first place the preprocessor looks is in the current directory. >using "-I-" allows one to override that (which, IMHO, is a creepily >bad idea to begin with but ... whatever). > > now, according to the man page above, the directories specified >before -I- are effectively override directories for such includes -- >that much i think i understand. and that second paragraph simply >reinforces that the current directory will *not* be used as the first >search location. > > but what isn't clear is whether the current directory will >*eventually* be searched. is it? if the quoted header file doesn't >exist in any of those "override" directories, will the local (current >directory) version be included? is it my imagination, or is that just >not clearly stated in the man page? > >rday > >p.s. can someone just reply to this email, to make sure my email is >working properly? weird things have been happening so i just want to >confirm things are getting out and being read. thank you kindly. > >-- > >======================================================================== >Robert P. J. Day Ottawa, Ontario, >CANADA > http://crashcourse.ca > >Twitter: >http://twitter.com/rpjday >LinkedIn: >http://ca.linkedin.com/in/rpjday >======================================================================== > > > > >------------------------------ > >Subject: Digest Footer > >_______________________________________________ >Linux mailing list >Linux [ at ] lists [ dot ] oclug [ dot ] on [ dot ] ca >http://oclug.on.ca/mailman/listinfo/linux > > >------------------------------ > >End of Linux Digest, Vol 135, Issue 16 >************************************** -- Sent from my Android device with K-9 Mail. Please excuse my brevity.