MS-DOS 如何将命令输出作为变量
MS-DOS how to get output of command as variable
我写了一个程序，returns 键码作为 DOS 的整数
但我不知道如何将它的输出作为变量。
注意：我使用的是 MS-DOS 7 / Windows 98，所以我不能使用 FOR /F 或 SET /P
有人知道我该怎么做吗？
Eric Pement here 描述了一些解决方案。但是，对于旧版本的 cmd，作者被迫使用外部工具。
例如，Douglas Boling 的 STRINGS 等程序工具允许使用以下代码：
echo Greetings! | STRINGS hi=ASK # puts "Greetings!" into %hi%
Richard Breuer 的 ASET 也是如此：
echo Greetings! | ASET hi=line # puts "Greetings!" into %hi%
另一种纯 DOS 解决方案需要将程序输出重定向到文件（在下面的示例中命名为 ANSWER.DAT），然后使用专门准备的批处理文件。引用上述页面：
[I]n the batch file we need to be able to issue the command
set MYVAR={the contents of ANSWER.DAT go here}. This is a difficult task, since MS-DOS doesn't offer an easy way to prepend "set MYVAR=" to a file [...]
Normal DOS text files and batch files end all lines with two consecutive bytes: a carriage return (Ctrl-M, hex 0D, or ASCII 13) and a linefeed (Ctrl-J, hex 0A or ASCII 10). In the batch file, you must be able to embed a Ctrl-J in the middle of a line.
Many text editors have a way to do this: via a Ctrl-P followed by Ctrl-J (DOS EDIT with Win95/98, VDE), via a Ctrl-Q prefix (Emacs, PFE), via direct entry with ALT and the numeric keypad (QEdit, Multi-Edit), or via a designated function key (Boxer). Other editors absolutely will not support this (Notepad, Editpad, EDIT from MS-DOS 6.22 or earlier; VIM can insert a linefeed only in binary mode, but not in its normal text mode).
If you can do it, your batch file might look like this:
@echo off
:: assume that the datafile exists already in ANSWER.DAT
echo set myvar=^J | find "set" >PREFIX.DAT
copy PREFIX.DAT+ANSWER.DAT VARIAB.BAT
call VARIAB.BAT
echo Success! The value of myvar is: [%myvar%].
:: erase temp files ...
for %%f in (PREFIX.DAT ANSWER.DAT VARIAB.BAT) do del %%f >NUL
Where you see the ^J on line 3 above, the linefeed should be embedded at that point. Your editor may display it as a square box with an embedded circle.
我写了一个程序，returns 键码作为 DOS 的整数 但我不知道如何将它的输出作为变量。
注意：我使用的是 MS-DOS 7 / Windows 98，所以我不能使用 FOR /F 或 SET /P
有人知道我该怎么做吗？
Eric Pement here 描述了一些解决方案。但是，对于旧版本的 cmd，作者被迫使用外部工具。
例如，Douglas Boling 的 STRINGS 等程序工具允许使用以下代码：
echo Greetings! | STRINGS hi=ASK # puts "Greetings!" into %hi%
Richard Breuer 的 ASET 也是如此：
echo Greetings! | ASET hi=line # puts "Greetings!" into %hi%
另一种纯 DOS 解决方案需要将程序输出重定向到文件（在下面的示例中命名为 ANSWER.DAT），然后使用专门准备的批处理文件。引用上述页面：
[I]n the batch file we need to be able to issue the command
set MYVAR={the contents of ANSWER.DAT go here}. This is a difficult task, since MS-DOS doesn't offer an easy way to prepend"set MYVAR="to a file [...]Normal DOS text files and batch files end all lines with two consecutive bytes: a carriage return (Ctrl-M, hex 0D, or ASCII 13) and a linefeed (Ctrl-J, hex 0A or ASCII 10). In the batch file, you must be able to embed a Ctrl-J in the middle of a line.
Many text editors have a way to do this: via a Ctrl-P followed by Ctrl-J (DOS EDIT with Win95/98, VDE), via a Ctrl-Q prefix (Emacs, PFE), via direct entry with ALT and the numeric keypad (QEdit, Multi-Edit), or via a designated function key (Boxer). Other editors absolutely will not support this (Notepad, Editpad, EDIT from MS-DOS 6.22 or earlier; VIM can insert a linefeed only in binary mode, but not in its normal text mode).
If you can do it, your batch file might look like this:
@echo off :: assume that the datafile exists already in ANSWER.DAT echo set myvar=^J | find "set" >PREFIX.DAT copy PREFIX.DAT+ANSWER.DAT VARIAB.BAT call VARIAB.BAT echo Success! The value of myvar is: [%myvar%]. :: erase temp files ... for %%f in (PREFIX.DAT ANSWER.DAT VARIAB.BAT) do del %%f >NULWhere you see the ^J on line 3 above, the linefeed should be embedded at that point. Your editor may display it as a square box with an embedded circle.