Running an Init on Target System (4 of 16)
Determining Install Status of DDs and Data
Next, the init determines which file's data dictionaries and data values
will be installed on the target system. Based on the parameters the developer
included in the init in combination with the environment encountered at the
target site, the installer is asked a series of questions for each file.
NOTE: With the one exception mentioned below, no changes are made
on the target system at this time. The answers obtained are saved to be used
later in the installation process when the target system is updated.
The exported files are checked one-by-one. What happens to each file is
described in the list that follows:
- The name of the file is displayed to the installer whether or not a
partial DD is being sent and whether or not data is coming with the file. If
there is not a file with the same file number on the target system, the DD will
be installed and the installer is next presented with the questions concerning
the installation of the data.
- If there is already a file under that number and the names are the
same, the init tells the installer.
NOTE: You already have the
'file name' File.
- If there is a file with that number, but the file names do not match,
the installer is asked if the name should be replaced. The default response is
NO. In the event of miss matched file names, the following instructions are
- If the installer is sure that the files are really the same and
that just the name has been changed, this question should be answered YES. In
this case, the init does a DIE call to change the name of the file on the
target system. (This is the only situation in which the target system is
altered during this phase of the install.) The init then continues with the
dialog as if the file names had matched in the first place.
- If the installer determines that the files are not the same and
answers NO, then the init asks if the incoming file should replace the file
currently on the system. If the installer answers NO to this question, the
current file will be left unchanged. However, this choice will result in the
installation of an incomplete package. Therefore, if this happens, the
installation should probably be stopped and the package developer
- If the installer chooses to replace the file on the target
system, the init asks if the current file's data and templates should be kept.
Based on the answers to these questions, the current DD (and optionally the
data and templates) will be deleted, before the new DD is brought in. A call to
DIU is set up to do the DD deletion and also to delete the data and templates
if the installer so instructs. See the description of
- If to this point the DD will be installed, the init checks if the
developer defined a screen to determine whether or not to install the DD. The
existence of a developer-defined screen overrides the installer's ability to
decide if the DD should be installed. If the screen exists and its conditions
are not met, the DD will not be installed but the init continues. The package
developer should indicate what to do when the screen stops the DD from
- If the developer decided to let the installer determine if the DD
will be installed, the init asks if an existing DD should be overwritten. If
the installer answers NO, the existing DD will be unchanged. Package developers
should indicate when it is okay to answer this question NO.
- If data is being brought with the DD and the package developer
decided to ask the question, the installer is asked whether to overwrite the
target system data or merge it with the incoming data. The package developer
determines whether data merges or overwrites; the installer can decide if the
data will be installed, not how it will be installed. The developer should
advise the installer on how to answer this question.
- If the developer did not give the installer the option of installing
the data or not, the init just indicates whether the data will merge with or
overwrite the current data.
Reviewed/Updated: March 10, 2007