FORM Compilation Steps in Oracle APPS

Set environment file on apps tier R12_BASE/ apps/ apps_st/ appl/
                                        APPS<sid>_<hostname>.env
Ensure that the $FORMS_PATH includes $AU_TOP/resource and $AU_TOP/resource/stub, for example            
                                        echo $FORMS_PATH
                                    /u01/oracle/DEV/apps/apps_st/appl/au/12.0.0/resource:
                                   /u01/oracle/DEV/apps/apps_st/appl/au/12.0.0/resource/stub
export FORMS_PATH and add AU_TOP/forms/US in FORMS_PATH like
                        export FORMS_PATH=$FORMS_PATH:$AU_TOP/forms/US
Change to form compilation executable directory (10.1.2 Oracle Home in R12)
                                        cd $ORACLE_HOME/bin
Compile the form
If you are using forms customizations (CUSTOM.pll) then run the command below to compile the form.
frmcmp_batch.sh module=<path to fmb file> userid=APPS/<PWD> output_file=<full path to fmx output file> module_type=form compile_all=special
For eg:-
frmcmp_batch.sh module=/u01/oracle/TEST/apps/apps_st/appl/au/12.0.0/forms/US/XXX.fmb userid=APPS/APPS output_file=/u01/oracle/TEST/apps/apps_st/appl/inv/12.0.0/forms/US/XXX.fmx module_type=form compile_all=special                
If you are NOT using forms customizations, then run the command below to compile the form.
frmcmp_batch.sh module=<path to fmb file> userid=APPS/<PWD> output_file=<full path to fmx output file> module_type=form
For eg:-
frmcmp_batch.sh module=/u01/oracle/TEST/apps/apps_st/appl/au/12.0.0/forms/US/XXX.fmb userid=APPS/APPS  output_file=/u01/oracle/TEST/apps/apps_st/appl/inv/
12.0.0/forms/US/XXX.fmx module_type=form