The vunpack program unpacks files from a COM file created by vpack. Its primary use is on UNIX systems, where the COM file is not self-extracting, though it may be used in VMS.
The vunpack program accepts a list of parameters as follows:
vunpack <file.com> [{source|pdf|imake|build|make|
test|repack|doc|std|system|unpack|all}]
or
vunpack <file.com> -f file.1 file.2 file.3
If you call the vunpack program with no parameters, the program will report an error and will tell you the proper syntax to use.
The first parameter tells vunpack which COM file to extract files from. The remaining (optional) parameters tell the program which file(s) to extract. You may extract more than one type of file, if desired, by putting more than one type on the command line, separated by spaces. If no parameters other than the COM file name are provided, the program unpacks all the files in the COM file.
The vunpack program will not automatically compile and link the program, but it can extract the imakefile so that you can create the BLD file (VMS) or makefile (UNIX) which can create the executable for you. See 2.3 Using the Generated VMS Build File or 2.4 Using the Generated UNIX makefile for details.
The vunpack program also allows you to extract a list of specified files from the COMfile. Instead of unpacking groups of files, by specifying " -f " and supplying a list of one or more file names, vunpack can unpack only the file(s) you need.
For example, if only host.c was needed from the view.com file:
vunpack view.com -f host.c
If you need all of the source files and the imakefile from VIEW.COM:
vunpack view. com source imake
The vunpack program will extract files from the COM file and put them in the current directory, but it will not alter the COM file in any way.