FAQ Compilation for Batch Processing Novices - China DOS Union Forum

First of all, welcome all DOS enthusiasts to enter the batch processing room of the China DOS Union to study and discuss issues.
If you have just registered an account, please read this article, which can help you avoid many unnecessary/repeated questions and posts.

If you are a new user just arriving, I will put forward a few small requirements:

1. Before posting for help, please search the forum first, because the problem you raise may have been solved at least more than once;
2. If after your own thinking and searching, you still haven't solved your problem, then post a help post. Be sure to pay attention that the title should express the main meaning of the post, so that more people will pay attention to your problem;
3. Do not insult the personality of others in the forum, which violates the forum rules.

Question0:
Experts, please come in!
Urgent!!!!!!!!!!
Kneeling to beg!!
Who can help me????
A very difficult problem!

Answer:
If the title of your post is like this, you can first take a look here:
http://www.cn-dos.net/forum/viewthread.php?tid=1415

Question1:
I see that there are many symbols in many batch processing codes, such as (% ^ |! ~), I don't know what their specific functions are?

Answer:
If you encounter a problem about symbols, you can refer to the following:
http://www.cn-dos.net/forum/viewthread.php?tid=30985

Question2:
What does a statement like "%date:~0,10%" mean?

Answer:
This is a variable intercepting function of CMD, which can intercept the characters at the specified position of the variable. For the specific usage, you can refer to the following post:
http://www.cn-dos.net/forum/viewthread.php?tid=25746

Question3:
What is variable delay, and what is the use of "Setlocal EnableDelayedExpansion" in batch processing?

Answer:
Refer to the following two posts, and I believe you will have a certain understanding of variable delay:
http://www.cn-dos.net/forum/viewthread.php?tid=20733
http://www.cn-dos.net/forum/viewthread.php?tid=28273

Question4:
The for command is so difficult, how to use it specifically?

Answer:
After carefully reading the following several posts, you will definitely master the common usages of the for command:
http://www.cn-dos.net/forum/viewthread.php?tid=19331
http://www.cn-dos.net/forum/viewthread.php?tid=13592
http://www.cn-dos.net/forum/viewthread.php?tid=33751
There are many posts with the use of for. If you have been lurking long enough, you will definitely master the usage of for!

Question5:
What does %%~fa in the for command mean?

Answer:
Enter for /? in the command line and look at the last part.
PS: The usage of many commands is included in their own help documents. As long as you read them carefully, you will definitely learn a lot.

Question6:
How to create an empty file?

Answer:
http://www.cn-dos.net/forum/viewthread.php?tid=22336

Question7:
How does batch processing execute a command after delay?

Answer:
http://www.cn-dos.net/forum/viewthread.php?tid=23475#pid140849

Question8:
What is redirection?

Answer:
http://www.cn-dos.net/forum/viewthread.php?tid=16942#pid115734

Question9:
The batch processing prompts that wget, sed or gawk are not internal commands or external commands. What should I do?

Answer:
wget, sed and gawk are all third-party tools. They need to be downloaded and placed in the system search path or the current directory to run. You can download them from the following special attachment post:
http://www.cn-dos.net/forum/viewthread.php?tid=25914

Question10:
What does set string=%string:AAA=BBB% mean?

Answer:
This is the character replacement function of cmd, that is, replacing the character "AAA" in the variable "string" with "BBB".

Question11:
What does "gtr" mean in if %str% gtr 255 command?

Answer:
This is the comparison operator of if:

EQU - equal
NEQ - not equal
LSS - less than
LEQ - less than or equal
GTR - greater than
GEQ - greater than or equal

[ Last edited by lxmxn on 2007-10-7 at 06:45 PM ]

Floor1　lxmxn	Posted 2007-10-03 20:29
版主　Posts 4,938　Credits 11,386
First of all, welcome all DOS enthusiasts to enter the batch processing room of the China DOS Union to study and discuss issues. If you have just registered an account, please read this article, which can help you avoid many unnecessary/repeated questions and posts. If you are a new user just arriving, I will put forward a few small requirements: 1. Before posting for help, please search the forum first, because the problem you raise may have been solved at least more than once; 2. If after your own thinking and searching, you still haven't solved your problem, then post a help post. Be sure to pay attention that the title should express the main meaning of the post, so that more people will pay attention to your problem; 3. Do not insult the personality of others in the forum, which violates the forum rules. Question0: Experts, please come in! Urgent!!!!!!!!!! Kneeling to beg!! Who can help me???? A very difficult problem! Answer: If the title of your post is like this, you can first take a look here: http://www.cn-dos.net/forum/viewthread.php?tid=1415 Question1: I see that there are many symbols in many batch processing codes, such as (% ^ \|! ~), I don't know what their specific functions are? Answer: If you encounter a problem about symbols, you can refer to the following: http://www.cn-dos.net/forum/viewthread.php?tid=30985 Question2: What does a statement like "%date:~0,10%" mean? Answer: This is a variable intercepting function of CMD, which can intercept the characters at the specified position of the variable. For the specific usage, you can refer to the following post: http://www.cn-dos.net/forum/viewthread.php?tid=25746 Question3: What is variable delay, and what is the use of "Setlocal EnableDelayedExpansion" in batch processing? Answer: Refer to the following two posts, and I believe you will have a certain understanding of variable delay: http://www.cn-dos.net/forum/viewthread.php?tid=20733 http://www.cn-dos.net/forum/viewthread.php?tid=28273 Question4: The for command is so difficult, how to use it specifically? Answer: After carefully reading the following several posts, you will definitely master the common usages of the for command: http://www.cn-dos.net/forum/viewthread.php?tid=19331 http://www.cn-dos.net/forum/viewthread.php?tid=13592 http://www.cn-dos.net/forum/viewthread.php?tid=33751 There are many posts with the use of for. If you have been lurking long enough, you will definitely master the usage of for! Question5: What does %%~fa in the for command mean? Answer: Enter for /? in the command line and look at the last part. PS: The usage of many commands is included in their own help documents. As long as you read them carefully, you will definitely learn a lot. Question6: How to create an empty file? Answer: http://www.cn-dos.net/forum/viewthread.php?tid=22336 Question7: How does batch processing execute a command after delay? Answer: http://www.cn-dos.net/forum/viewthread.php?tid=23475#pid140849 Question8: What is redirection? Answer: http://www.cn-dos.net/forum/viewthread.php?tid=16942#pid115734 Question9: The batch processing prompts that wget, sed or gawk are not internal commands or external commands. What should I do? Answer: wget, sed and gawk are all third-party tools. They need to be downloaded and placed in the system search path or the current directory to run. You can download them from the following special attachment post: http://www.cn-dos.net/forum/viewthread.php?tid=25914 Question10: What does set string=%string:AAA=BBB% mean? Answer: This is the character replacement function of cmd, that is, replacing the character "AAA" in the variable "string" with "BBB". Question11: What does "gtr" mean in if %str% gtr 255 command? Answer: This is the comparison operator of if: EQU - equal NEQ - not equal LSS - less than LEQ - less than or equal GTR - greater than GEQ - greater than or equal [ Last edited by lxmxn on 2007-10-7 at 06:45 PM ]

Floor2　my3439955	Posted 2007-10-03 20:36
中级用户　Posts 99　Credits 272
relatively comprehensive

Floor3　viplsd	Posted 2007-10-04 13:34
新手上路　Posts 1　Credits 1
Well well well well well well well well well well well well well well well

Floor4　putao	Posted 2007-10-05 15:28
初级用户　Posts 41　Credits 80
China DOS Union. There are really many experts.

Floor5　zwdeee	Posted 2007-10-07 08:08
初级用户　Posts 54　Credits 153
Great, it seems that the link under "Question2:" was posted incorrectly.

Floor6　lxmxn	Posted 2007-10-07 18:46
版主　Posts 4,938　Credits 11,386
Thanks to zwdeee for correction, the link has been fixed.

Floor7　huanghourun	Posted 2007-10-10 00:46
新手上路　Posts 3　Credits 6
Can learn a lot of things

Floor8　z83001	Posted 2007-10-10 22:15
新手上路　Posts 13　Credits 19
Thanks for the reminder. Newcomers can benefit a lot from learning more.

Floor9　regvip2008	Posted 2007-10-23 16:58
初级用户　Posts 87　Credits 187
Thanks for sharing, learned it~~

Floor10　blue812	Posted 2007-10-29 17:27
初级用户　Posts 29　Credits 57
It's very good and very helpful for our new learners. Thanks!

Floor11　jfsy	Posted 2007-11-01 12:59
初级用户　Posts 14　Credits 26
Great! I'm learning batch processing, thank you for providing.

Floor12　honeyxiaoyi	Posted 2007-11-03 19:37
新手上路　Posts 3　Credits 6
Let's also learn batch processing... Support China DOS Union

Floor13　lhweiy	Posted 2007-11-03 22:45
新手上路　Posts 10　Credits 19
Thanks to the landlord. Learn and study.

Floor14　hongying915	Posted 2007-11-07 23:05
新手上路　Posts 7　Credits 14
It's much more convenient. Thanks.

Floor15　wangmail	Posted 2007-11-08 23:24
新手上路　Posts 9　Credits 17
Points are for looking at other things