सम्प्रेषण (Sampreshan) संगच्छध्वं सं वदध्वं सं वो मनांसि जानताम्‌। देवा भागं यथा पूर्वे संजानाना उपासते॥ ऋग्वेद 12/191.4

Installing new version of Grails is easy. However it's quite a pain to make it running on Cygwin. The problem is as follows:

Jdk 5 introduced "javaagent" as one of the JAVA_OPTS and it has been used in running Grails 2. Shell scripts convert $GRAILS_HOME in cygwin format for running grails. So for instance if $GRAILS_HOME is c:/grails, it becomes '/cygdrive/c' in cygwin format. This makes

AGENT_STRING=-"-javaagent:$GRAILS_HOME/lib/com.springsource.springloaded/springloaded-core/jars/springloaded-core-0.8.4.jar

to something like this:

$ echo $AGENT_STRING
$ "-javaagent:/cygdrive/c/grails/lib/com.springsource.springloaded/springloaded-core/jars/springloaded-core-0.8.4.jar

which JRE doesn't understand while executing 'java'. It expects -javaagent value to be something like 'c:/grails/lib/com.springsource.springloaded/springloaded-core/jars/springloaded-core-0.8.4.jar'.

To make it work, following changes need to be done in $GRAILS_HOME/bin/startGrails script:

Introduce a new variable something like GRAILS_HOME_FORWARD_SLASH before making any change to environment based $GRAILS_HOME.

# For Cygwin, ensure paths are in UNIX format before anything is touched

GRAILS_HOME_FORWARD_SLASH=`echo $GRAILS_HOME|sed 's/[\]/\//g'`

Also change the way AGENT_STRING is defined as follows:

AGENT_STRING="-javaagent:$GRAILS_HOME_FORWARD_SLASH/lib/com.springsource.springloaded/springloaded-core/jars/springloaded-core-0.8.4.jar -noverify -Dspringloaded=profile=grails"

This change lets you work with Grails 2 now on Cygwin