FNDLOAD is very  useful oracle provided utility to migrate core oracle apps objects (Flex  fields,Concurrent program,responsibility,user,profiles,messages,request  group.......forms personalization etc) from one instance to other.This  post is all about FNDLOAD utility. 
Oracle  provided all setup objects being stored in FND tables and shared   across the application.The name FNDLOAD - to load/download objects  to/from FND Tables.
1) Upload objects - 
 FNDLOAD apps_user_name/apps_password 0 Y UPLOAD $Control_file $Object_name.ldt  
2) Download objects - 
FNDLOAD apps_user_name/apps_password 0 Y DOWNLOAD $Control_file $Object_name.ldt [Parameters]
Parameters -  
$Object_TYPE [$Object_TYPE_Name="Your Object Name"] APPLICATION_SHORT_NAME=$'XXXXX' [$SubObject_TYPE] [$SubObject_TYPE_Name="Your sub Object Name"]
$Control_file  => Control file is .lct file specific to object.Give the complete  patch of file or download file at same location.most of the cases it is  available at $FND_TOP/patch/import
$Object_name.ldt  => Downloaded file will be saved with this name
 $Object_TYPE => downloaded object type (REQUEST_GROUP,PROGRAM etc)
Sub  Object Type is required in case object is holding many objects and  requirement is to download single sub object. Ex - Request Group  contains many concurrent program entry, to download request group  holding only your conc prog, use sub object type as program and give  your program name. 
 
Below is the FNDLOAD command for different objects - 
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FNDLOAD example for few frequently used objects 
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XML Data Definition and Template 
FNDLOAD  apps/appspwd 0 Y DOWNLOAD $XDO_TOP/patch/115/import/xdotmpl.lct  DATADEFTEMPLATE.ldt XDO_DS_DEFINITIONS APPLICATION_SHORT_NAME='XXXXX'  DATA_SOURCE_CODE='Your Data Definition Code'
Concurrent Program 
FNDLOAD  apps/appspwd 0 Y DOWNLOAD $FND_TOP/patch/115/import/afcpprog.lct  file_name.ldt PROGRAM APPLICATION_SHORT_NAME="prod"  CONCURRENT_PROGRAM_NAME="concurrent name"
Request Set 
FNDLOAD  apps/appspwd 0 Y DOWNLOAD $FND_TOP/patch/115/import/afcprset.lct  file_name.ldt REQ_SET APPLICATION_SHORT_NAME="prod"  REQUEST_SET_NAME="request set"
Request Group  
FNDLOAD  apps/appspwd 0 Y DOWNLOAD $FND_TOP/patch/115/import/afcpreqg.lct  file_name.ldt REQUEST_GROUP REQUEST_GROUP_NAME="request group"  APPLICATION_SHORT_NAME="prod"
Single Program from Request Group
FNDLOAD  apps/appspwd O Y DOWNLOAD  $FND_TOP/patch/115/import/afcpreqg.lct DATALOADERFILE.ldt REQUEST_GROUP  REQUEST_GROUP_NAME="Your Request Group name"  APPLICATION_SHORT_NAME="Your Request Group Application short name"  REQUEST_GROUP_UNIT UNIT_NAME="Your concurrent program short name"
Single Message
FNDLOAD apps/appspwd 0 Y DOWNLOAD $FND_TOP/patch/115/import/afmdmsg.lct YOURLDTFILENAME.ldt FND_NEW_MESSAGES APPLICATION_SHORT_NAME='XXXXX' MESSAGE_NAME='YOUR MESSAGE NAME'
Message 
FNDLOAD apps/appspwd 0 Y DOWNLOAD $FND_TOP/patch/115/import/afmdmsg.lct YOURLDTFILENAME.ldt FND_NEW_MESSAGES APPLICATION_SHORT_NAME='XXXXX' 
Responsibility  FNDLOAD  apps/appspwd O Y DOWNLOAD $FND_TOP/patch/115/import/afscursp.lct  file_name.ldt FND_RESPONSIBILITY RESP_KEY="responsibility
Value set 
FNDLOAD  apps/appspwd 0 Y DOWNLOAD $FND_TOP/patch/115/import/afffload.lct  file_name.ldt VALUE_SET FLEX_VALUE_SET_NAME="value set name"
Value set with values
FNDLOAD  apps/appspwd 0 Y DOWNLOAD $FND_TOP/patch/115/import/afffload.lct  file_name.ldt VALUE_SET_VALUE FLEX_VALUE_SET_NAME="value set name"
   
Menu 
FNDLOAD apps/appspwd  0 Y DOWNLOAD $FND_TOP/patch/115/import/afsload.lct file_name.ldt MENU MENU_NAME="menu_name" 
Profiles 
FNDLOAD  apps/appspwd 0 Y DOWNLOAD $FND_TOP/patch/115/import/afscprof.lct  file_name.ldt PROFILE PROFILE_NAME="profile option"  APPLICATION_SHORT_NAME="XXXXX"
KFF - Key Flex Fields   
FNDLOAD  apps/appspwd 0 Y DOWNLOAD $FND_TOP/patch/115/import/afffload.lct  file_name.ldt KEY_FLEX  P_LEVEL=?COL_ALL:FQL_ALL:SQL_ALL:STR_ONE:WFP_ALL:SHA_ALL:CVR_ALL:SEG_ALL?  APPLICATION_SHORT_NAME="XXXXX" ID_FLEX_CODE="key flex code"  P_STRUCTURE_CODE="structure name"
DFF - Descriptive Flex Fields 
FNDLOAD  apps/appspwd 0 Y DOWNLOAD $FND_TOP/patch/115/import/afffload.lct  file_name.ldt DESC_FLEX P_LEVEL=?COL_ALL:REF_ALL:CTX_ONE:SEG_ALL?  APPLICATION_SHORT_NAME="xxxxx" DESCRIPTIVE_FLEXFIELD_NAME="desc flex  name" P_CONTEXT_CODE="context name"
 Lookup 
FNDLOAD  apps/appspwd 0 Y DOWNLOAD $FND_TOP/patch/115/import/aflvmlu.lct  file_name.ldt FND_LOOKUP_TYPE APPLICATION_SHORT_NAME="xxxxx"  LOOKUP_TYPE="lookup name"
Printer Style  
FNDLOAD  apps/appspwd 0 Y DOWNLOAD $FND_TOP/patch/115/import/afcppstl.lct  file_name.ldt STYLE PRINTER_STYLE_NAME="printer style name"