在自己对句柄操作的理解基础上
编写了以下句柄操作模拟代码
大家可以在cmd中挂参数多次运行模拟
看是否符合实际句柄操作后的结果
那么如何判断一个句柄的指向呢
echo 1<&要判定的句柄号 is con
如果显示 con ,那么句柄值为con
否则为nul或者文件
:: 句柄模拟.cmd - 模拟运算句柄操作后的句柄状态
:: qzwqzw - 2009-6-12
@echo off & setlocal EnableDelayedExpansion
if == (
echo. 这是句柄操作示例, 模拟运算进行几次句柄操作后的句柄状态
echo --------------------- call %~n0 "1>&2" "3>nul" ---------------------
call %0 "1>&2" "3>nul" >nul
set 句柄
echo.
echo --------------------- call %~n0 "1>&2" "4>file1.txt" ---------------------
call %0 "1>&2" "4>file1.txt" >nul
set 句柄
echo.
echo --------------------- call %~n0 "1>&2" "5>con" ---------------------
call %0 "1>&2" "5>con" >nul
set 句柄
echo.
pause
goto :eof
)
set "0=con" & set "1=con" & set "2=con"
for %%h in (%句柄%) do set %%h
echo.----- 起始状态 Initiation state -----
for %%h in (0 1 2 3 4 5 6 7 8 9) do set/p=%%h=!%%h! <nul
echo.
echo.----- 预处理 Pre-process -----
:loop
if == goto :end
echo.----- %1 -------
set "_tmp=%~1"
set _句柄=%_tmp:~0,1%
set _句柄_2=
set _dev=
if "%_tmp:~2,1%"=="&" (set _句柄_2=%_tmp:~3%) else (set _dev=%_tmp:~2%)
for %%h in (0 1 2 3 4 5 6 7 8 9) do (
if "!%%h!"=="" (
set/p=b: %_句柄%=^>%%h : <nul
set "%%h=!%_句柄%!"
set bak_%%h=%_句柄%
goto :set
)
)
:set
for %%h in (0 1 2 3 4 5 6 7 8 9) do set/p=%%h=!%%h! <nul
echo.
if defined _dev (
set/p=a: %_dev%=^>%_句柄% : <nul
set %_句柄%=%_dev%
) else if defined _句柄_2 (
set/p=a: %_句柄_2%=^>%_句柄% : <nul
set %_句柄%=!%_句柄_2%!
)
for %%h in (0 1 2 3 4 5 6 7 8 9) do set/p=%%h=!%%h! <nul
echo.
shift
goto :loop
:end
echo.----- 后处理 Post-process -----
for %%h in (0 1 2 3 4 5 6 7 8 9) do (
if not "!bak_%%h!"=="" (
set/p=r: !bak_%%h!^<=%%h : <nul
set !bak_%%h!=!%%h!
set %%h=
set bak_%%h=
for %%h in (0 1 2 3 4 5 6 7 8 9) do set/p=%%h=!%%h! <nul
echo.
)
)
set 句柄=
for %%h in (0 1 2 3 4 5 6 7 8 9) do set 句柄=!句柄! "%%h=!%%h!"
endlocal & set 句柄=%句柄%
echo.----- 结束状态 End Status -----
for %%h in (%句柄%) do set/p=%%~h <nul
echo.
Last edited by qzwqzw on 2009-6-13 at 21:12 ]
