# HG changeset patch # User Andrew John Hughes # Date 1280166213 -3600 # Node ID c64dd66292dbf81529514a8ae3eec46109ecad2d # Parent 07fdd12537a6b010affc9a79f05e0b8194b9cd04 Update INSTALL documentation and configure help. 2010-07-21 Andrew John Hughes * INSTALL: Updated, with documentation of new options and removal of outdated information. * acinclude.m4: (WITH_OPENJDK_SRC_DIR): Add '=DIR' to the configure help. (AC_CHECK_FOR_OPENJDK): Add '[=DIR]' to the configure help. (AC_CHECK_WITH_TZDATA_DIR): Remove broken expansion of ${DEFAULT} in configure help, replacing it with the value used. * configure.ac: Fix default in configure help for NIO2 and plugin options. diff -r 07fdd12537a6 -r c64dd66292db ChangeLog --- a/ChangeLog Wed Jul 21 18:17:59 2010 +0100 +++ b/ChangeLog Mon Jul 26 18:43:33 2010 +0100 @@ -1,3 +1,15 @@ +2010-07-21 Andrew John Hughes + + * INSTALL: Updated, with documentation + of new options and removal of outdated information. + * acinclude.m4: + (WITH_OPENJDK_SRC_DIR): Add '=DIR' to the configure help. + (AC_CHECK_FOR_OPENJDK): Add '[=DIR]' to the configure help. + (AC_CHECK_WITH_TZDATA_DIR): Remove broken expansion of ${DEFAULT} + in configure help, replacing it with the value used. + * configure.ac: + Fix default in configure help for NIO2 and plugin options. + 2010-07-21 Andrew John Hughes * README: Updated. diff -r 07fdd12537a6 -r c64dd66292db INSTALL --- a/INSTALL Wed Jul 21 18:17:59 2010 +0100 +++ b/INSTALL Mon Jul 26 18:43:33 2010 +0100 @@ -7,8 +7,10 @@ The build requirements are as follows: -GNU libgcj 4.3.0 (or equivalent 1.5 class library, such as GNU Classpath >= 0.95) -Eclipse Java Compiler +A bootstrap JDK, either: + - GNU libgcj 4.3.0 (or equivalent class library based on GNU Classpath >= 0.95) for --with-gcj-home mode (the default) + - IcedTea6 for --with-openjdk mode +Eclipse Java Compiler (ecj) CUPS libX11 (libXp, libXtst, libXi, libXt) Freetype2 @@ -27,96 +29,344 @@ libXinerama-devel giflib-devel libpng-devel -libjpeg-devel = 6b +libjpeg-devel >= 6b zlib-devel +xulrunner-devel (can be disabled using --disable-plugin) rhino (can be disabled using --without-rhino) - -For building the PulseAudio based mixer, you will need -pulseaudio-libs-devel >= 0.9.11 - -For building VisualVM, you will need -netbeans = 6.5 - -For building the zero-assembler port (see below), you will need libffi. - -For building the Shark JIT, you will need LLVM 2.5 or current SVN. - -For building with systemtap support (--enable-systemtap), you will need -systemtap-sdt-devel (available since systemtap 0.9.5). This also needs -the --with-abs-install-dir configure option to make sure the hotspot.stp.in -tapset gets the correct installation location for the libjvm.so, it -defaults to the root of the j2sdk-image build dir otherwise (but then -you cannot move that to another location without adjusting the paths -in the tapset/hotspot.stp file. For example: - --enable-systemtap --with-abs-install-dir=/usr/lib/jvm/java-1.6.0-openjdk -(Java method tracing works starting with systemtap 0.9.9) +libffi (for --enable-zero or on archs other than x86/x86_64/sparc) +pulseaudio-libs-devel >= 0.9.11 (for --enable-pulse-java) +LLVM 2.5 or later (for --enable-shark) +systemtap-sdl-devel >= 0.9.5 (for --enable-systemtap, Java method tracing requires systemtap >= 0.9.9) +netbeans = 6.5 (for --enable-visualvm) See ./configure --help if you need to override the defaults. -To bootstrap IcedTea with ecj and a Classpath-based JDK such as GCJ: -autoreconf +To bootstrap IcedTea with ecj and a GNU Classpath-based JDK: +./autogen.sh ./configure make -To build IcedTea with an older version of IcedTea or OpenJDK, use: -autoreconf -./configure --with-openjdk - to specify the location use --with-openjdk=/path/to/icedtea] +The following locations are checked for a GNU Classpath-based JDK: + * /usr/lib/jvm/java-gcj + * /usr/lib/jvm/gcj-jdk + * /usr/lib/jvm/cacao +in that order. + +To build IcedTea with an older version of IcedTea6, use: +./autogen.sh +./configure --with-openjdk make -There is currently no install target. +The following locations are checked for an IcedTea6 JDK: + * /usr/lib/jvm/java-openjdk + * /usr/lib/jvm/icedtea6 + * /usr/lib/jvm/java-6-openjdk + * /usr/lib/jvm/openjdk + * /usr/lib/jvm/java-icedtea +in the order given above. + +Note that IcedTea7 can not be used to build IcedTea6. -IcedTea ends up in openjdk/build/- when the build completes. -Example instantiations of - include linux-i586, linux-amd64 and linux-ppc64. +There is currently no install target. IcedTea ends up in +openjdk/build/- when the build completes. Example +instantiations of - include linux-i586, linux-amd64 and +linux-ppc64. -Rebuilding The IcedTea Plugs ----------------------------- +Most targets in IcedTea creat stamp files in the stamps directory to +determine what and when dependencies were compiled. Each target has a +corresponding clean-x target which removes the output and the stamp +file, allowing it to be rebuilt. For example, stamps/rt.stamp (alias +rt) builds the bootstrap classes needed in the bootstrap build and +clean-rt removes the classes and the stamp file. + +Build Modification Options +========================== + +The build process may be modified by passing the following options +to configure: -When IcedTea is initially built, it creates stamp files in the stamps directory -to determine what and when dependencies were compiled. For example, to rebuild -the rt plugs certain files need to be deleted before restarting the build. - - - If the rt plugs have been modified, delete stamps/rt-class-files.stamp. - - If a new class has been added to the rt plugs, delete - rt-source-files.txt so it can be recreated with the new class list. +* --disable-docs: Don't build the Javadoc documentation. +* --with-openjdk-src-dir: Copy the specified OpenJDK tree, rather than + downloading and extracting a tarball. +* --disable-optimizations: Build with -O0. +* --enable-hg: Checkout the OpenJDK tree from Mercurial, rather than + downloading and extracting a tarball. +* --with-gcj: Compile ecj to native code with gcj prior to building. +* --with-openjdk: Perform a quick (no bootstrap) build using an installed + copy of IcedTea6. If a directory is not specified, a check against + the list presented above is performed. +* --with-parallel-jobs: Run the specified number of parallel jobs when + building HotSpot and the JDK. +* --with-netbeans-home: The location of NetBeans for use in the VisualVM build, + defaults to /usr/share/netbeans. +* --with-ant-home: The location of Ant, defaults to /usr/share/ant. +* --with-pkgversion=PKG: Include the specified distro package information in + the output of java -version. +* --with-gcj-home: Perform a full bootstrap build using an installed + copy of a GNU Classpath JDK such as gcj. If a directory is not specified, + a check against the list presented above is performed. +* --with-java: Specify the location of a 'java' binary. By default, the path + is checked for gij and java. +* --with-ecj: Specify the location of a 'ecj' binary. By default, the path + is checked for ecj, ecj-3.1, ecj-3.2 and ecj-3.3. +* --with-javac: Specify the location of a 'javac' binary. By default, the path + is checked for javac. +* --with-jar: Specify the location of a 'jar' binary. By default, the path + is checked for gjar and jar. +* --with-javah: Specify the location of a 'javah' binary. By default, the path + is checked for gjavah and javah. +* --with-rmic: Specify the location of a 'rmic' binary. By default, the path + is checked for grmic and rmic. +* --with-ecj-jar: Specify the location of an ecj JAR file. By default, the + following paths are checked: + - /usr/share/java/eclipse-ecj.jar + - /usr/share/java/ecj.jar + - /usr/share/eclipse-ecj-3.{2,3,4,5}/lib/ecj.jar +* --with-xalan2-jar: Specify the location of a xalan2 JAR file. By default, the + following paths are checked: + - /usr/share/java/xalan-j2.jar + - /usr/share/java/xalan2.jar + - /usr/share/xalan/lib/xalan.jar +* --with-xalan2-serializer-jar: Specify the location of a xalan2 serializer JAR file. + By default, the following paths are checked: + - /usr/share/java/xalan-j2-serializer.jar + - /usr/share/xalan-serializer/lib/serializer.jar + - /usr/share/java/serializer.jar +* --with-xerces2-jar: Specify the location of a xerces2 JAR file. By default, the + following paths are checked: + - /usr/share/java/xerces-j2.jar + - /usr/share/java/xerces2.jar + - /usr/share/xerces-2/lib/xercesImpl.jar + - /usr/share/java/xercesImpl.jar +* --with-openjdk-src-zip: Specify the location of the OpenJDK tarball to avoid downloading. +* --with-hotspot-src-zip: Specify the location of the HotSpot tarball to avoid downloading. +* --with-alt-jar: Use the specified jar binary in the second stage rather than the one just built. +* --with-cacao-home: Specify the location of an installed CACAO to use rather than downloading + and building one. +* --with-cacao-src-zip: Specify the location of a CACAO tarball to avoid downloading. +* --with-hg-revision: Specify a hg revision to use (as opposed to tip) with the --enable-hg option. +* --with-tzdata-dir: Specify the location of Java timezone data, defaulting to /usr/share/javazi. +* --with-netbeans: Specify the location of NetBeans for VisualVM, defaulting to the netbeans on the path. +* --with-abs-install-dir: The final install location of the j2sdk-image, for use in the SystemTap tapset. -To view all targets that create stamp files, see -Makefile.am (section 'All Stamped Targets'). +Other options may be supplied which enable or disable new features. +These are documented fully in the relevant section below. + +* --enable-visualvm: Build VisualVM. +* --enable-pulse-java: Build the PulseAudio sound provider. +* --disable-xrender: Don't include the XRender pipeline. +* --enable-nio2: Include the NIO2 backport. +* --enable-systemtap: Include support for tracing using systemtap. +* --enable-nss: Enable the NSS security provider. +* --enable-cacao: Replace HotSpot with the CACAO VM. +* --enable-shark: Build the Shark LLVM-based JIT. +* --enable-zero: Build the zero assembler port on x86/x86_64/sparc platforms. +* --enable-plugin: Build the browser plugin. +* --enable-npplugin: Build the new NPPlugin. +* --with-hotspot-build: The HotSpot to use, defaulting to 'original' i.e. hs14 as bundled with OpenJDK. +* --with-rhino: Include Javascript support using Rhino. +* --with-additional-vms=vm-list: Additional VMs to build using the system described + below. + +Testing +======= -The Zero Assembler Port ------------------------ +IcedTea6 includes support for running the test suite included with +OpenJDK, using the in-tree copy of JTReg. Invoking 'make check' will +cause the HotSpot, JDK and langtools test suites to be run. The +individual test suites may be run using the check-hotspot, check-jdk +and check-langtools targets respectively. + +VisualVM +======== + +IcedTea6 supports the downloading and compilation of VisualVM 1.1.1 +via the --enable-visualvm option. This requires NetBeans 6.5. The +build takes place following that of IcedTea, which is used to compile +VisualVM, and the result is installed in the SDK image created by the +OpenJDK build (i.e. openjdk/build/-/j2sdk-image). + +The PulseAudio provider +======================= + +IcedTea6 includes an implementation of the javax.sound.* APIs using +PulseAudio which can be enabled using --enable-pulse-java. The resulting +provider is org.classpath.icedtea.pulseaudio.PulseAudioMixerProvider. + +Xrender Support +=============== -Gary Benson has developed a port of the interpreter included in the -HotSpot virtual machine which avoids using any assembly language. As -a pure C++ interpreter, it should be possible to build this on most -architectures and have a working (albeit slow) version of OpenJDK. -Successful builds have been made on ppc, ppc64 and arm. The zero -assembler port is enabled by default on platforms other than x86, -x86_64 and sparc. To enable it on these platforms, use the ---enable-zero option. +IcedTea6 includes support for an Xrender-based rendering pipeline +developed by Clemens Eisserer (http://linuxhippy.blogspot.com/). This +is compiled by default, and can be disabled using --disable-xrender. +To actually use the pipeline, the sun.java2d.xrender property needs to +be set to true, e.g. by passing the -Dsun.java2d.xrender=True option +to java. + +NIO2 Backport +============= + +IcedTea6 includes a backport of NIO2 from OpenJDK7; see +http://openjdk.java.net/projects/nio/. This provides support for +asynchronous I/O and an improved file system API, providing access to +POSIX file permissions, timestamps, extended attributes and ACLs and +allowing directories to be watched. This is enabled using the +--enable-nio2 option. + +As new classes can not be added to the java.* and javax.* namespace of +the 1.6 API, the new java.nio classes are contained in +org.classpath.icedtea.java.nio, so code will needed to be adjusted to +work with the backport. -Gary is now working on a JIT called Shark to provide better -performance on platforms which need to use the zero port. A -preliminary version of this is now included with IcedTea and can be -built with the --enable-shark option. +SystemTap +========= + +IcedTea6 includes work to allow the existing DTrace probes included in +OpenJDK to be used with SystemTap. This is enabled using the +--enable-systemtap option, and requires version 0.9.5 or later (0.9.9 +or later if you want Java method tracing). The tapset needs to know +the final install location of the JDK, so the --with-abs-install-dir +should also be used to specify this. If not set, it defaults to the +in-tree location of openjdk/build/-/j2sdk-image and requires +manual changes to tapset/hotspot.stp to work from elsewhere. For +example, if you plan to install the resulting build in +/usr/lib/jvm/java-1.6.0-openjdk, then you should specify +--enable-systemtap +--with-abs-install-dir=/usr/lib/jvm/java-1.6.0-openjdk. + +NSS Security Provider +===================== + +OpenJDK includes an NSS-based security provider in the form of +sun.security.pkcs11.SunPKCS11. However, as this needs to know the +location of the NSS installation it should use, it is not enabled +in normal OpenJDK builds. As IcedTea can detect NSS using configure, +it can simplify the process of enabling this provider. If --enable-nss +is specified, then a configuration file for the NSS provider will be +generated and installed, and the provider turned on. CACAO ------ +===== + +IcedTea6 can use CACAO as the virtual machine, as opposed to HotSpot. +One advantage of this is that CACAO has a JIT implementation for +more platforms than HotSpot, including ppc, ppc64, arm and mips. +When --enable-cacao is specified, CACAO will be downloaded and built, +followed by the JDK portion of OpenJDK resulting in a CACAO+OpenJDK +image in openjdk/build/-/j2sdk-image. The --with-cacao-home +option can be used to specify the use of an existing CACAO install +instead, and --with-cacao-src-zip/dir options exist to allow the use +of a pre-downloaded zip or source tree respectively. + +Zero & Shark +============ + +IcedTea6 includes a zero assembler port of HotSpot, which avoids +architecture-specific code as much as possible, allowing an +interpreter to be built and run on most platforms (albeit very +slowly). As HotSpot only includes JITs for x86, x86_64 and SPARC, the +zero assembler port is automatically enabled on all other +architectures. On x86, x86_64 and SPARC, it may be built using +--enable-zero. + +To overcome the performance issues inherent in zero, a LLVM-based JIT +called Shark has been developed. This performs Just-In-Time compilation +on any architecture supported by LLVM. To enable it, pass the option +--enable-shark to configure. Please note that Shark is still in +development and builds are still likely to fail at present. + +Please also note that HotSpot 14 (the default) must be used with Zero +and Shark. We don't support the use of HotSpot 11. See the +documentation of the hotspot-build option below for more details. + +The Browser Plugin +================== + +IcedTea6 currently includes two browser plugins; a new plugin based on +NPRuntime and an older deprecated plugin used in previous releases. +By default, neither will be built as the plugin is no longer supported +or maintained as part of the IcedTea6 1.6 series. To use the plugin, +we recommend you upgrade to at least IcedTea6 1.7.4, where the new +NPPlugin will be built by default. + +If you do wish to enable the plugin in this release, it can be built +by passing the --enable-npplugin option to configure for the new +NPPlugin or --enable-plugin for the old plugin. + +For debugging, the environment variable ICEDTEAPLUGIN_DEBUG should be +set to 'true'. This will produce output on the console from the C++ +side, and output from the Java side in $HOME/.icedteaplugin/java.stdout +and $HOME/.icedteaplugin/java.stderr. It also starts the debug server +on port 8787. + +Support for Different Versions of HotSpot +========================================= -The CACAO virtual machine (http://cacaovm.org) can be used as an -alternative to the HotSpot virtual machine. One advantage of this is -that it already provides a JIT for many platforms to which HotSpot has -not yet been ported, including ppc, ppc64, arm and mips. To use CACAO -as the VM, use the --with-cacao option. This will download CACAO -0.99.3 during the build. To use a different version, use ---with-cacao-home= to point to an existing installation which use -the Sun VM interface. +IcedTea allows the version of HotSpot provided with the upstream build +drop to be replaced with another. Support for this is provided by the +--with-hotspot-build option which causes IcedTea to probe the +hotspot.map file for an entry with the given build name. The +hotspot.map file maps the name to a changeset from a given repository +URL. During the build, it downloads HotSpot from +${URL}/archive/${CHANGESET}.tar.gz and the resulting file is verified +using the MD5 sum stored in hotspot.map. + +New build selections may be provided by providing further mappings in +the hotspot.map file. The name can be anything +e.g. 'shiny_new_hotspot'. This is simply used to map the argument to +--with-hotspot-build to the values in the file and to apply +appropriate patches (see patches/hotspot, $HSBUILD is available in +Makefile.am for obtaining the build name). The special value +'original' is used for patches/hotspot/original to denote those for +the upstream HotSpot; this value does not appear in hotspot.map. + +The changeset and URL should refer to a valid HotSpot tree when used +as above. The required values can be obtained from a local checkout +or by using the web interface. The simplest way to calculate the MD5 +sum is to download the tarball and then run the 'md5sum' application +on it. The resulting value should be added to hotspot.map. + +As with the OpenJDK build tarballs, the location of an alternate zip +can be specified using --with-hotspot-src-zip. This skips the +download stage and just verifies that the zip's MD5 sum matches that +of the requested build. -Building additional virtual machines ------------------------------------- +At present, two versions of HotSpot are officially supported. These +are HotSpot 11 ('original') which is provided by the upstream OpenJDK +tarball, and 'default', which is used in hotspot.map to provide the +latest version of HotSpot 14. Thus, either no hotspot-build option, +--with-hotspot-build without an argument or +--with-hotspot-build=default provides the latest supported hs14, while +--without-hotspot-build or --with-hotspot-build=original uses the +upstream HotSpot. + +Note that HotSpot 11 ('original') is not supported for use with Zero +or Shark. + +Javascript Support +================== + +IcedTea6 adds Javascript support via the javax.script API by using +an existing installation of Rhino. Support is enabled by default, +with the following locations being searched for a Rhino JAR file: + +* /usr/share/java/rhino.jar +* /usr/share/java/js.jar +* /usr/share/rhino-1.6/lib/js.jar + +A JAR file can instead be specified using the --with-rhino option, +or support may be disabled by specifying --without-rhino. + +Note that the final installed JAR file is a modified version with the +namespace prefixed by 'sun.' as in the proprietary Oracle JDK. This +avoids conflicts between the JDK's copy of Rhino and any used by other +applications. + +Building Additional Virtual Machines +==================================== Although IcedTea can be built multiple times to use a different virtual -machine, addtional VM's can be built without building the other components +machine, additional VMs can be built without building the other components multiple times. On architectures where hotspot is available, use @@ -125,46 +375,10 @@ --with-additional-vms=cacao to build the additional VM's. It's not possible to build cacao as the default VM, and zero as additional VM. +To build zero as the default VM and shark as an additional VM, use + --enable-zero --with-additional-vms=shark The additional VM's are available by calling the java with the option -`-cacao' or `-zero' (for shark as well), or by calling the java tools with -`-J-'. - -Support for different versions of HotSpot ------------------------------------------ - -IcedTea allows the version of HotSpot provided with the upstream build -drop to be replaced with another. Support this is provided by the ---with-hotspot-build option which causes IcedTea to probe the -hotspot.map file for an entry with the given build name. The -hotspot.map file maps the name to a changeset from the repository -http://hg.openjdk.java.net/hsx/hsx14/master/ which it downloads from -http://hg.openjdk.java.net/hsx/hsx14/master/archive/${CHANGESET}.tar.gz. -The resulting download is verified using the MD5 sum stored in -hotspot.map. - -New build selections may be provided by providing further mappings in -the hotspot.map file. The name can be anything -e.g. 'shiny_new_hotspot'. This is simply used to map the argument to ---with-hotspot-build to the values in the file and to apply -appropriate patches (see patches/hotspot, $HSBUILD is available in -Makefile.am for obtaining the build name). The special value -'original' is used to denote the upstream HotSpot and does not appear -in hotspot.map. The changeset should map a valid changeset in the -HotSpot Express master repository (URL shown above). These can be -obtained from a local checkout or using the web interface. The -simplest way to calculate the MD5 sum is to download the tarball and -then run the 'md5sum' application on it. The resulting value should -be added to hotspot.map. - -As with the OpenJDK build tarballs, the location of an alternate zip -can be specified using --with-hotspot-src-zip. This skips the -download stage and just verifies that the zip's MD5 sum matches that -of the requested build. - -At present, the build name 'default' is used in hotspot.map to provide -the latest version of HotSpot 14 in place of the version of HotSpot 11 -provided by upstream. Thus, --with-hotspot-build is enabled by -default, and either --without-hotspot-build or ---with-hotspot-build=original is required to revert to the upstream -HotSpot. +`-cacao', `-zero' or `-shark', or by calling the java tools with +`-J-'. If the build was configured with '--enable-shark', +use `-Xint' to just use the zero VM. diff -r 07fdd12537a6 -r c64dd66292db acinclude.m4 --- a/acinclude.m4 Wed Jul 21 18:17:59 2010 +0100 +++ b/acinclude.m4 Mon Jul 26 18:43:33 2010 +0100 @@ -222,7 +222,7 @@ [ AC_MSG_CHECKING(for an OpenJDK source directory) AC_ARG_WITH([openjdk-src-dir], - [AS_HELP_STRING(--with-openjdk-src-dir,specify the location of the openjdk sources)], + [AS_HELP_STRING(--with-openjdk-src-dir=DIR,specify the location of the openjdk sources)], [ OPENJDK_SRC_DIR=${withval} AC_MSG_RESULT(${withval}) @@ -1008,7 +1008,7 @@ [ AC_MSG_CHECKING([for an existing OpenJDK installation]) AC_ARG_WITH([openjdk], - [AS_HELP_STRING([--with-openjdk], + [AS_HELP_STRING([--with-openjdk[=DIR]], [perform a quick build with an installed copy of OpenJDK])], [ if test "x${withval}" = xno @@ -1049,7 +1049,7 @@ DEFAULT="/usr/share/javazi" AC_MSG_CHECKING([which Java timezone data directory to use]) AC_ARG_WITH([tzdata-dir], - [AS_HELP_STRING(--with-tzdata-dir,set the Java timezone data directory [[default=${DEFAULT}]])], + [AS_HELP_STRING(--with-tzdata-dir,set the Java timezone data directory [[default=/usr/share/javazi]])], [ if test "x${withval}" = x || test "x${withval}" = xyes; then TZDATA_DIR_SET=yes diff -r 07fdd12537a6 -r c64dd66292db configure.ac --- a/configure.ac Wed Jul 21 18:17:59 2010 +0100 +++ b/configure.ac Mon Jul 26 18:43:33 2010 +0100 @@ -93,8 +93,8 @@ AC_MSG_CHECKING([whether to build the browser plugin]) AC_ARG_ENABLE([plugin], - [AS_HELP_STRING([--disable-plugin], - [Disable compilation of browser plugin])], + [AS_HELP_STRING([--enable-plugin], + [Enable compilation of the browser plugin])], [enable_plugin="${enableval}"], [enable_plugin="no"]) AM_CONDITIONAL(ENABLE_PLUGIN, test "x${enable_plugin}" = "xyes") AC_MSG_RESULT(${enable_plugin}) @@ -106,7 +106,7 @@ AC_MSG_CHECKING([whether to build the new experimental browser plugin based on npruntime]) AC_ARG_ENABLE([npplugin], [AS_HELP_STRING([--enable-npplugin], - [Enable compilation of browser plugin (automatically disables default plugin)])], + [Enable compilation of the new browser plugin (automatically disables default plugin)])], [enable_npplugin="${enableval}"], [enable_npplugin="no"]) AM_CONDITIONAL(ENABLE_NPPLUGIN, test "x${enable_npplugin}" = "xyes") AC_MSG_RESULT(${enable_npplugin}) @@ -146,8 +146,8 @@ AC_MSG_CHECKING(whether to include NIO2 support) AC_ARG_ENABLE([nio2], - [AS_HELP_STRING([--disable-nio2], - [Disable inclusion of backported NIO2])], + [AS_HELP_STRING([--enable-nio2], + [Enable inclusion of backported NIO2])], [ENABLE_NIO2="${enableval}"], [ENABLE_NIO2='no']) AM_CONDITIONAL([ENABLE_NIO2], [test x$ENABLE_NIO2 = xyes]) AC_MSG_RESULT(${ENABLE_NIO2})