Softpanorama (slightly skeptical) Open Source Software Educational Society

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Softpanorama University Library

The Orthodox File Manager (OFM) Paradigm

by Dr Nikolai Bezroukov

Classic OS/2 implementations

Technically OS/2 is superior to Windows 95.  Generally OS/2 is more close to UNIX  than Windows 95 and like UNIX has decent command line interface and large library of command line programs. Os/2 GNU ports are of very high quality and usually are up to date. 

OS/2 file systems (both FAT-based and HPFS)  also has unique and a very interesting concept of  file attributes -- so called extended attributes. If I remember correctly the initial idea was to based on the fact that at least half of  the sectors in the last cluster are empty and can be used for storage of useful information about the file. But it was implemented differently and can be considered as a database for a particular file. And in many respects this concept makes OS/2 file system behave like general purpose database. For example extended attributes like .SUBJECT, .COMMENT and .KEYPHRASES can be used as a descriptor for the file -- much more powerful and clean implementation of descriptors that hacks like descript.ion in 4DOS or treeinfo.  Other example is storing of interpreted Rexx as an extended attribute -- the idea that makes running of REXX scripts much faster that scripts in Unix or NT.

Unfortunately Os/2 file systems does not support links natively(if it would do so, it would be more powerful than UNIX filesystem), but free extension to HPFS (the Toronto Virtual File System) provided for links for directories.  

Os/2 is very popular among FIDO sysops, so the number of OFMs implementations is second only to DOS/Windows. I have found almost ten OFM implementations in the Hobbes OS/2 archive.  At least four OFMs discussed in DOS/Windows section of the paper have native OS/2 implementations. Among them is  EFC,  JetCommander, MC and Norton Commander for OS/2 (the latter is a discontinued commercial product). Other OS/2-based  OFM implementations include:

• FC. The leading COFM implementation for OS/2.
• Larsen Commander
• F file manager
• JC - Jet Commander by Frank Klosek  (already discussed in classical OFM section)
• DirMaster.
• fm2 - file manager from Barefoot Productions.
• nemo - Captain Nemo.
• os2c -OS/2 Commander.

OS/2 supports powerful macro/script language -- REXX. And it's rather strange that there were no attempts to integrate REXX into OFM implementation on OS/2.  That makes OS/2 implementations less interesting. So we will discuss only one OS/2 implementation - FC.