Although the materials all say that it can read things from files, there are no examples. Now I have a text file with only one number. I want to read it out and assign it to a variable. How to do it? I tried set var=<a.txt, which doesn't work. Hope to get some ideas or materials!
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中国DOS联盟论坛 » DOS学习入门 & 精彩文章 （教学室） » Who knows the usage of the redirection commands < and << in Dos?
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Original Poster
Posted 2006-11-24 09:51 · 中国 陕西 西安 电信
Floor 2
Posted 2008-09-19 14:17 · 中国 北京 联通
Help to top up. I also want to know how to do it. Most of the things in the forum are >.
Floor 3
Posted 2008-11-27 16:15 · 中国 上海 黄浦区 电信
">" and ">>" are both output redirections. However, ">>" appends the content to be output to the end of the document. For example:
@echo off
dir > d:\1.txt
pause
@echo off
dir >> d:\1.txt
pause
You can see the difference by having a look.
@echo off
dir > d:\1.txt
pause
@echo off
dir >> d:\1.txt
pause
You can see the difference by having a look.
Floor 4
Posted 2008-11-27 17:22 · 美国 惠普HP
It is suggested to ask questions in the Batch Processing Room
Floor 5
Posted 2008-11-27 19:59 · 中国 上海 杨浦区 电信
Hehe, I don't think this is only related to batch processing. Redirecting command lines can also be used.
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投票调查：
http://www.cn-dos.net/forum/viewthread.php?tid=46187
本人尚未解决的疑难问题：
http://www.cn-dos.net/forum/viewthread.php?tid=15135
http://www.cn-dos.net/forum/viewthread.php?tid=47663
http://www.cn-dos.net/forum/viewthread.php?tid=48747
DOS NEVER DIES !
投票调查：
http://www.cn-dos.net/forum/viewthread.php?tid=46187
本人尚未解决的疑难问题：
http://www.cn-dos.net/forum/viewthread.php?tid=15135
http://www.cn-dos.net/forum/viewthread.php?tid=47663
http://www.cn-dos.net/forum/viewthread.php?tid=48747
Floor 6
Posted 2008-11-28 21:39 · 中国 北京 联通
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< is input redirection, providing the internal response of the software. The content of dir.txt has only one byte which is D. For example, xcopy adir bdir < dir.txt. When prompted "Does 2 specify a file name or directory name on the target (F = File, D = directory)", the answer "D" will automatically become the answer and the copy continues.
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Posted 2008-11-28 21:43 · 中国 北京 联通
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Originally posted by wwmmc at 2008-11-27 16:15:
">" ">>"
Both are output redirections
However, ">>" appends the content to be output to the end of the document
For example:
@echo off
dir > d:\1.txt
pause
@echo off
...
There are several other uses for the output redirection ">", such as
dir > PRN
This sends the content output by dir directly to the printer (only printers using the LPT port)
And the following
pkunzip aa.zip c:\tools > nul
This means no decompression information is output during the decompression of aa.zip
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Floor 8
Posted 2008-11-28 21:56 · 中国 黑龙江 大兴安岭地区 联通
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">" is output; ">>" is append; "<" is input.
Floor 9
Posted 2009-02-10 13:45 · 中国 天津 电信
Hope there are some experts to give a few examples
Floor 10
Posted 2009-02-12 22:35 · 中国 甘肃 张掖 电信
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Take it back and Google it a bit!
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