1 Notes on the MS-DOS Perl port
6 [0. First copy the files in the msdos directory into the parent
11 Perl has been compiled under MS-DOS using the Microsoft
12 C compiler version 5.1. Before compiling install dir.h as
13 <sys/dir.h>. You will need a Unix-like make program (e.g.
14 pdmake) and something like yacc (e.g. bison). You could get
15 away by running yacc and dry running make on a Unix host,
16 but I haven't tried it. Compilation takes 12 minutes on a
17 20MHz 386 machine (together with formating the manual), so
18 you will probably need something to do in the meantime. The
19 executable is 272k and the top level directory needs 1M for
20 sources and about the same ammount for the object code and
23 The makefile will compile glob for you which you will
24 need to place somewhere in your path so that perl globbing
25 will work correctly. I have not tried all the tests or the
26 examples, nor the awk and sed to Perl translators. You are
27 on your own with them. In the eg directory I have included
28 an example program that uses ioctl to display the charac-
29 teristics of the storage devices of the system.
33 The MS-DOS version of perl has most of the functional-
34 ity of the Unix version. Functions that can not be provided
35 under MS-DOS like sockets, password and host database
36 access, fork and wait have been ommited and will terminate
37 with a fatal error. Care has been taken to implement the
38 rest. In particular directory access, redirection (includ-
39 ing pipes, but excluding the pipe function), system, ioctl
40 and sleep have been provided.
42 [Files currently can be edited in-place provided you are cre-
43 ating a backup. However, if the backup coincidentally has
44 the same name as the original, or if the resulting backup
45 filename is invalid, then the file will probably be trashed.
48 perl -i~ script makefile
49 perl -i.bak script file.dat
51 because (1) MS-DOS treats "makefile~" and "makefile" as the
52 same filename, and (2) "file.dat.bak" is an invalid filename.
53 The files "makefile" and "file.dat" will probably be lost
54 forever. Moral of the story: Don't use in-place editing
57 2.1. Interface to the MS-DOS ioctl system call.
59 The function code of the ioctl function (the second
60 argument) is encoded as follows:
62 - The lowest nibble of the function code goes to AL.
63 - The two middle nibbles go to CL.
64 - The high nibble goes to CH.
66 The return code is -1 in the case of an error and if
69 - for functions AL = 00, 09, 0a the value of the register DX
70 - for functions AL = 02 - 08, 0e the value of the register AX
71 - for functions AL = 01, 0b - 0f the number 0.
73 See the perl manual for instruction on how to distin-
74 guish between the return value and the success of ioctl.
76 Some ioctl functions need a number as the first argu-
77 ment. Provided that no other files have been opened the
78 number can be obtained if ioctl is called with
79 @fdnum[number] as the first argument after executing the
82 @fdnum = ("STDIN", "STDOUT", "STDERR");
84 for ($i = 3; $i < $maxdrives; $i++) {
86 @fdnum[$i - 1] = "FD$i";
89 2.2. Binary file access
91 Files are opened in text mode by default. This means
92 that CR LF pairs are translated to LF. If binary access is
93 needed the `binary' function should be used. There is
94 currently no way to reverse the effect of the binary func-
95 tion. If that is needed close and reopen the file.
97 2.3. Interpreter startup.
99 The effect of the Unix #!/bin/perl interpreter startup
100 can be obtained under MS-DOS by giving the script a .bat
101 extension and using the following lines on its begining:
104 @perl %0.bat %1 %2 %3 %4 %5 %6 %7 %8 %9
107 (Note that you will probably want an absolute path name in
112 Diomidis Spinellis <dds@cc.ic.ac.uk>