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Library file -- TURBO.TPL

In both Pascal environments, a library file is a file consisting of units available to all Pascal programs. In the p-System, any file containing code segments and the segment dictionary block may be designated a library file, and both the compiler and the runtime system can be directed to as many of them as needed.

Turbo Pascal 5.0 has at this date only one library file, TURBO.TPL(for Turbo Pascal Library). Others could theoretically be constructed with Turbo's library manager, but the compiler is not yet able to use them.

When Turbo Pascal is executed, the entire library file is read into memory and held there. Therefore, to gain much-needed compile-time memory, all but ``essential'' units are removed from TURBO.TPL. ``Essential'' units are either those Turbo must have, such as SYSTEM, or those whose names are longer than 8 characters. The latter results from a conflict between Turbo Pascal's expectations of the DOS filesystem and the way in which PC-NFS simulates DOS drives, preventing Turbo Pascal from finding these units on network drives.