IPF, INF and HLP-files

IPF files (Information Presentation Facility) are the source format of the IBM help format. The IPF syntax has got some similarity to HTML. Both languages are part of the SGML markup language family. The IPF syntax is not as clear as the HTML syntax and it is verbose and somewhat tedious to write.

IBM help is the help format of OS/2 and IBM PC-DOS 7. It's also used on Windows platforms, especially if IBM programs for platform-independent software development are used. Of all Hypertext formats, it's the fastest and has got the best functionality.

IBM help files have got the extension INF or HLP. INF files can be viewed alone. The HLP format is like the INF format, but enables links from the described program to the hypertext. HLP files are part of the program.

Hypermake generates IPF files. The automatically generated IPF file is the source file for the IBM program IPFC[IPFC generates INF- and HLP-files from the IPF source. IPFC.EXE is part of every programming development system for OS/2. At my system, the necessary files are IPFC.EXE, IPFC20.INF and IPFCEXMP.INF; there's also a directory IPFC with language-specific data. The Windows version is part of the IBM Visual Age C++ for Windows package.].

IBM INF and HLP files are compact binary files. The viewers of these files are compact and very fast. IBM INF viewers are available for OS/2 (of course, that's the format of all OS/2 docu), for Win16 and for DOS. The Win16 viewer is part of the "Just add Warp" package, you need the files LIBIPFX.DLL, VIEW.EXE and VIEWH.HLP. The DOS viewer is part of IBM DOS 7 and there's also a Freeware program (VIEW01.ZIP Compuserve OS2DF1).

In comparison to HTML or Winhelp3 browsers the IBM INF viewers have got some powerful features with a particular benefits for large documents:

• the Index is part of the binary INF file format
• the content, too. Subchapters can be expanded and re-expanded like in a directory tree
• very fast text searching: Every word has only one occurence in the binary INF format. From this word there are pointers to the location of the text. You can search some MB of text in only one second - the user gets a window with all chapters containing the word.
• Several INF files can be put together by commandline parameters of the viewer. The user sees one big help file with one content and one index.
  

If you are a Windows user and interested in this Hypertext format, then you can download a (16 bit) Freeware viewer (250 k), see
ftp://ftp.leo.org/pub/comp/os/windows/win3.11/utils/viewers
If you need an Hypermake generated IBM INF file to test with, simply upload my OS/2 Freeware program CLEAR or my Shareware program 4allCalc.