The Amyuni PDF Converter is our Printer Driver that enables you to convert any documents to PDF format. If you have any questions about installing and using the Amyuni PDF Converter please post them here.
There are a couple of minor differences between the 2 flags.
1) Concatenate was introduced with v1 of PDF Converter (a long time ago...), whereas AppendExisting was introduced in a later release. AppendExisting comes with various other flags that give more options to the developer and end-user when the file already exists:
ConfirmOverwrite : If the file exists, confirm before overwriting.
AppendExisting : If the file exists, append to existing file.
AddDateTime : If the file exists, add date and time to file name.
AddIdNumber : If the file exists, add ID number to file name.
2) Concatenate has no effect on the user-interface, this flag is for developers only. AppendExisting affects the printer properties and the SaveAs windows (if AppendExisting is set, the corresponding check-box will be checked in the UI.) For developers who have the limited user-interface version of PDF Converter, there will of course be no effect on user-interface.
In short, a developer can choose either of the 2 flags but Concatenate will take precedence and cancel the effect of the other flags. I.e. if Concatenate and AddIdNumber are set, AddIdNumber will not have any effect. Although not useful, there is no harm in setting the 2 flags together.
A bit of history about why these flags were named this way: Concatenate is a developer specific term (we developers are used to concatenating strings and arrays!) End-users were often confused by the word Concatenate and the term Append is more meaningful to them, so we preferred using the term Append in later versions of PDF Converter.
Amyuni Development Team
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