Migration influence in ABAP program

Question

hi guys,
We are going for migration from 4.6C (Op.sys - HP-Unix, DB-Oracle 8.0) to 4.6C(Op.sys-Solaris,DB-Oracle 9.0).
We need to analyse what are the changes required to be considered before migration.
I guess below things are basic things
1-External command.
2-OS level application execution command.
3-OPEN file path(logical path,physical path)
other than this is there any thing i have to considered for OS and Database difference inside ABAP programs.
appreciate if you Can give me check list...if possible
Pls suggest me.
thanks.
Ambi.

Answer 1

MESSAGE  ext TYPE mtype ... .
This variant sends a character string contained in text as a message of the message type specified in mtype. You can enter a character-type data object text, which will be used as a short text for the message. Only the first 300 characters in text are taken into account. No long text can be defined for a message of this type.
For mtype, a character-type data object is expected, which must contain the message type in capital letters. Invalid message types generate an untreatable exception.
Notes
: In this variant, the additions WITH and INTO are not allowed in message_options.
If field symbols or formal parameters of the type any or data are specified for text, these must be of character type when the statement is executed. The syntactically identical variant MESSAGE oref cannot be executed with generically typed field symbols or formal parameters.
Because the system fields sy-msgid and sy-msgno are filled unspecifically when a character string is entered, this variant should only be used on rare occasions if the content of the system fields is not required for identification of the message. Otherwise, in all cases in which messages are transferred (for example, from function modules) or logged (for example, in batch input) using these system fields, language-independent access to the message text would be lost.
Example
: Output of an exception text as an information message.
DATA: oref TYPE REF TO cx_sy_arithmetic_error,
      text TYPE string.
TRY.
  CATCH cx_sy_arithmetic_error INTO oref.
    text = oref->get_text( ).
    MESSAGE text TYPE 'I'.
ENDTRY.