Script processing

You can customize the actions taken during installation by delivering installation scripts with your package. The decision on which type of script to use depends upon when the action is needed during the installation process. As a package is installed, pkgadd(ADM) performs the following steps:

1. Executes the request script.

   This is the only point at which your package can solicit input from the installer.

2. Executes the preinstall script.

3. Installs the package objects.

   Installation occurs class-by-class and class action scripts are executed accordingly. The list of classes operated upon and the order in which they should be installed is initially defined with the CLASSES parameter in your pkginfo(F) file. However, your request script can change the value of CLASSES.

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   NOTE: Be absolutely sure that the CLASSES environment variable in the pkginfo file lists all the package's class names from the prototype file, or that they are conditionally added to the CLASSES variable (as appropriate) by the request script. Only those class names appearing in the CLASSES environment variable at the time installation begins will be installed. Any files belonging to a class name not found in CLASSES at the time the installation begins will not be installed.

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4. Executes the postinstall script.

When a package is being removed, pkgrm(ADM) performs these steps:

1. Executes the preremove script.

2. Executes the removal class action scripts.

   Removal also occurs class-by-class. As with the installation class action scripts, if more than one removal script exists, they are processed in the reverse order in which the classes were listed in the CLASSES parameter at the time of installation.

3. Executes the postremove script.

The request script is not processed at the time of package removal. However, its output (a list of parameter values) is saved and so is available to removal scripts.