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- ;
- M2Z3INS.COM
-
- Size (recs) CRC Version Author/Latest Issue Disk
- 19k (150) 5AF6 1.0 Ed Jackson 10/87 Z3COM6
-
- 1- Usage 2- Notes
-
- M2Z3INS "installs" Turbo Modula2 programs which have been linked into .COM
- files in a ZCPR3 environment, ZCPR3.3 environment, or CP/M environment. This
- is accomplished by patching the GetEnv procedure which MUST be included in the
- root segment of the TM2 .COM file. A subsequent call to this procedure will
- return the address of the resident environment descriptor or, for CP/M, a NIL
- address and a string of up to 16 characters. The string is intended to be
- used as a file name for TCAP information but can be used for any other purpose
- desired.
-
- M2Z3INS is written in Turbo Modula2. The basic approach was suggested by
- Steven Cohen.
- :1
-
-
- Usage:
-
- To use the installation program you MUST include the GetEnv procedure in
- your TM2 code. Compile the code and link it into a .COM file. After the
- installation process, a call to GetEnv will return the address of the
- environment descriptor and the 16 char string.
- :2
-
- M2Z3INS Notes:
-
- a. In ZCPR3.3 systems the TM2 program becomes self adapting... that is,
- after installing it with the M2Z3INS program it can be moved to any
- ZCPR3.3 system and it will correctly find the environment descriptor.
- In a ZCPR3.3 environment the address of the environment descriptor is
- placed in register HL by the loader after loading the .COM file. The
- .COM file is patched by this installation program so that register HL is
- saved in the GetEnv procedure.
-
- b. In ZCPR3.0 systems the TM2 program must be reinstalled if moved to
- another computer to guarantee that it will correctly find the
- environment descriptor. In a ZCPR3.0 environment the address of the
- environment descriptor is obtained from the *.ENV file that is peculiar
- to the target system.
-
-
- M2Z3INS Notes (continued):
-
- c. In CP/M systems there is, of course, no environment descriptor but the
- installation program permits installing a 16 char string in the TM2
- program. M2Z3INS patches the environment descriptor address to NIL and
- the 16 char string to the value specified at installation time. The
- intended use of the string is to install the name of a file containing
- system environment info (TCAP?), but its use is not restricted. Where
- an environment descriptor is available, the 16 char string is empty.
-
- d. The system works by searching the TM2 .COM file 1 char at a time for a
- unique marker (don't be surprised if it takes rather a long time on
- floppy disks!). Just after the marker, the .COM file is patched to
- insert the address of the resident environment descriptor and a 16 char
- array.
-
- e. Since many ZCPR systems place the environmen descriptor at 0FE00h, this
- is used as the default value in GetEnv.