Additional Topics > External Development Guide > IDLInternals - Error Handling > Looking up a Message Code by Name

# Looking Up a Message Code by Name

Given a message block pointer and the name of a message from that block, the IDL_MessageNameToCode() function returns the message code that corresponds to it. This is especially useful for dynamically loadable modules that need to throw errors from the IDL core block. The actual error codes are subject to change between IDL releases, so looking them up this way at run-time allows a given DLM to work with different IDL versions.

int IDL_MessageNameToCode(IDL_MSG_BLOCK block, char *name)

where:

### block

Message block name should be translated against, or NULL to use the default core IDL block.

### name

The message name for which the code is desired. Name is case sensitive, and should usually be specified as uppercase. IDL_MessageNameToCode () returns the message code, or 0 if it is not found.