Changes between Version 141 and Version 142 of FAQ

Timestamp:

Nov 13, 2015, 1:20:01 PM (8 years ago)

Author:

ryandesign (Ryan Carsten Schmidt)

Comment:

minor edits to /usr/local section including adding a note to that trace mode doesn't work on El Capitan yet

FAQ

@@ -76 +76 @@
 === So with MacPorts under /opt/local I can use /usr/local freely? === #usrlocal
 
-No, not entirely. Even with MacPorts living elsewhere, `/usr/local` can still interfere.
+No. Even though MacPorts is installed elsewhere, software installed in `/usr/local` can still interfere with MacPorts.
 Some software (especially the GNU auto* tools and gcc) looks into `/usr/local` for external headers, libraries, and binaries. Certain ports might (and do) fail to build because during their build something incompatible is found and picked up
 from `/usr/local`. Good ports avoid this by explicitly specifying `--with-libfoo=/opt/local/lib/` or explicitly disabling all such possible dependencies altogether with `--disable-foo` or `--without-bar` but not all ports are able to do that.
 
 If you ask on a MacPorts mailing list about a port failing to build because it chokes on something
-that it found and picked up in `/usr/local` you will probably be advised to temporarily rename
-`/usr/local` to make it disappear entirely for the duration of the build.
-Obviously, this wouldn't be possible to do if MacPorts itself lived under `/usr/local`.
-
-Note that starting with 2.3.0, MacPorts can automatically hide `/usr/local` (and all other files a port does not depend on) from ports' build systems. This feature is called trace mode and is activated by providing the `-t` flag to `port`, e.g.
+that it found and picked up in `/usr/local` you will be asked to remove what you've installed in `/usr/local`
+or to temporarily rename `/usr/local` to make it disappear entirely for the duration of the build.
+
+Note that starting with 2.3.0, MacPorts can automatically hide `/usr/local` (and all other files a port does not depend on) from ports' build systems.
+This feature is called trace mode and is activated by providing the `-t` flag to `port`, e.g.
 {{{
 sudo port -t install <portname>
 }}}
 You'll notice a small performance penalty when using trace mode, and a very small number of ports will fail to build due to the changes in the environment (currently, only the `go` and `sbcl` ports are known to be affected). Warnings about sandbox violations are normal when using trace mode. If a port fails to build in trace mode, the problem is very likely a bug. You should file a ticket if none exists yet.
+
+Note that trace mode in MacPorts 2.3.4 and earlier is not compatible with El Capitan.
+A fix has been committed in r141420 but not yet released in a stable version of MacPorts.
 
 === How do I remove or uninstall MacPorts? === #uninstall