hi,
Customer exit -
R/3 enhancement concept allows you to add your own functionality to SAP’s standard business applications without having to modify the original applications.
SAP creates customer exits for specific programs, screens, and menus within standard R/3 applications. These exits do not contain any functionality. Instead, the customer exits act as hooks. You can hang your own add-on functionality onto these hooks.
If you want to enhance the functionality of your SAP System, you should take advantage of the exits available in standard applications. There are two main reasons why you should use exits rather than modifying SAP software yourself. Add-ons attached to exits have the advantage that:
● They do not affect standard SAP source code.
When you add new functionality to your SAP System using SAP’s exits, you do not alter the source code of standard SAP programs in any way. The code and screens you create are encapsulated as separate objects. These customer objects are linked to standard applications, but exist separately from SAP’s standard software package.
● They do not affect software updates.
When you add new functionality to your SAP System using SAP’s exits, your objects (called customer objects) must adhere to strict naming conventions. When it comes time to upgrade a to a new software release, customer objects’ names ensure that they will not be affected by any changes or new additions to the standard software package.
Customer exits are not available for all programs and screens found in the SAP System. You can only use customer exits if they already exist in the SAP System. You find find more information about locating applications with pre-defined exits in Locating Applications that have Exits.
http://help.sap.com/saphelp_nw04/helpdata/en/c8/19762743b111d1896f0000e8322d00/content.htm
http://help.sap.com/saphelp_bw21c/helpdata/en/f1/0a56f5e09411d2acb90000e829fbfe/content.htm
SMOD and CMOD ARE USED FOR ENHANCEMENTS LIKE USER EXITS ,MENU EXITS ,SCREEN EXITS.
SAP uses an User Exit (SMOD/CMOD) in order to make an enhancement of customers a lot more convenient. There are very many user exits available within SAP.
When using an user exit, the system does NOT become modified what happens when you start changing SAP for your needs.
So, it is very interesting to make use of all options, that leave the SAP system as unmodified as possible. Therefore, you should always check the available user exits in the area for your needed enhancements.
You can activate user exits in the SAP transactions SMOD and CMOD. There you can check for the appropiate user exit and insert the new enhanced code in function modules for your needs.
TA CMOD -> Utilities -> SAP Enhancements -> F8 Execute)
SMOD is just to see all the enhancements in the sap system.
CMOD is the customer projects where enhancements are implemented. If you want to implement any enhancements then you will create a project and assign the enhancement and do the coding in exits.
To customize an existing SAP application we have been provided the user exits by SAP. These exits are packaged under enhancements. You choose an enhancement according to your requirements e.g. enhancement MM06E005 is used for adding custom field in me21/me21n. SAP has limited no of enhancements for any transactions, you have to choose only from them to cater your requiement you cant create them.
After selecting your enhancements you have to inherit them in your project in CMOD. Thereafter you do coding and other things like making your subscreens or adding fields to standard tables in respective exits.
To see the effect of your whole project you must activate each componnents of your enhancements.
refer following sites
http://help.sap.com/saphelp_nw04/helpdata/en/eb/3e7ceb940e11d295df0000e82de14a/content.htm
http://www.sap-img.com/abap/what-is-the-difference-between-smod-and-cmod.htm
http://www.sap-img.com/abap/field-exits-smod-cmod-questions-and-answers.htm
http://www.easymarketplace.de/userexit.php?Area=4soi
please reward points if helpful,
shylaja
Edited by: shylaja puchala on Jan 15, 2008 12:49 PM
Bluesky
