For loop in batch file to read text file
If you need to read a file line by line and perform some action with each line — then you should use a while read line construction in Bash, as this is the most proper way to do the necessary. In this article i will show the general syntax of the while read line construction in Bash and an example of how to read a file line by line from the Linux command line.
I will also show an example of the Bash script that reads an input file line by line and prints each line with some appended text. Cool Tip: Make your Bash script interactive! The LINE in this construction — is the name of a variable that stores the line during each loop iteration.
You can change it to the more appropriate name, depending on the contents of a FILE. Lets create a Bash script, that takes a path to a file as an argument and prints "This is a line:" before the each line of this file. Create an empty readfile. Cool Tip: Do not be a bore! I knew there was a way to do it without programming it. Actually programming it would make it look cleaner. It is easy to do and the system calls are inside the executable.
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Batch file commands
View our Welcome Guide to learn how to use this site. Joined Aug 16, Messages 2. I'm having trouble with the FOR command syntax to read lines of an input file into separate variables and I was hoping you can help. Suppose an input file had Var1: a Var2: b what is the syntax in a batch file to set the variable Var1 to the value "a" and the variable Var2 to the value "b"? It seems like a common enough need, but I couldn't find many examples out there Thanks Jason.
Change your preferences any time. Stack Overflow for Teams is a private, secure spot for you and your coworkers to find and share information. I'm having trouble figuring out the best way to accomplish the first 2 steps. My FOR loop seems to stop after reading the very first line:. You want to preserve each line in its entirety.
TO parse the path you want to use the FOR variable modifiers. The toggling of delayed expansion is just to protect against a possible! If you know that no path contains! EDIT - this code has been modified significantly since Aacini pointed out that I misread the requirements. It should satisfy the requirements now. The timestamp coding may seem irrelevant to your issue, but I left it because it's a good example of dissecting the filename itself.
Different shells may have different results. In the end, the delayedexpansion command wasn't necessary. It was the sub-routine that fixed my issues with variables inside the loop. That could possibly be because of my OS ver. Win 8. This works. Don't write quotes to results. Learn more. For loop in batch file reading a file of File Paths Ask Question. Asked 8 years, 2 months ago. Active 4 years ago. Viewed 5k times.The DO command is then executed with the parameter s set to the token s found.
The option s must be contained within "a pair of quotes". This option is useful when dealing with a filenameset that is a long filename containing spaces, it allows you to put double quotes around the filename. Filenames which don't contan spaces can still be referenced without using quotes. SKIP will skip processing a number of lines from the beginning of the file. The default end-of-line character is a semicolon ';' when the FOR command reads a text file or even a character stringany line that STARTS with the eol character will be ignored.
In other words it is treated as a comment. You can use almost any character as a delimiter, but they are case sensitive. One special case is using a quote " as delimiter. The letters used for tokens are case sensitive. For this reason it is recommended to always place delims as the last option before the closing quotation, it is much easier to see what is happening with one space or no spaces at the end of the string. A string of text will be treated just like a single line of input from a file, the string must be enclosed in double quotes or single quotes with usebackq.
Echo just the date from the following string. To specify an exact set of files to be processed, such as all. Many of the newer commands and utilities e. To convert the file format use the TYPE command. FOR does not, by itself, set or clear the Errorlevel. FOR is an internal command. Related: FOR - Loop commands.
FOR - Loop through a set of files in one folder. IF - Conditionally perform a command. Powershell: ForEach-Object - Loop for each object in the pipeline.I have a text file which contains exe files. Sample content of the text file a. I need to read and execute xINT. Here number is variable changes as version changes but xINT.
I am stuck here. Need help to fix this. When you write I have a text file which contains exe files I suspect you actually mean I have a text file which contains a number of exe file names. If so then extracting their names using a batch file is messy.
To select that one line of output, you can search for the text "loss" which is always presentthen use the Tokens parameter to select the number of lost packets, here this is 0 but it will vary each time you run the command.
You can override this default parsing behavior by specifying the "options" parameter. The options must be contained within "quotes".
How To loop through each line in a text file using a Batch Dos?
This option is useful when dealing with a command that already contains one or more straight quotes. SKIP will skip processing a number of lines from the beginning of the file. The default end-of-line character is a semicolon ';' when the FOR command reads a text file or even a character stringany line that STARTS with the eol character will be ignored.
In other words it is treated as a comment. You can use almost any character as a delimiter, but they are case sensitive. One special case is using a quote " as delimiter. The letters used for tokens are case sensitive. Also consider the case where the command fails, the FOR command will trap the error, but the DO clause is never reached - this means the variable will not be changed.
This can cause subtle bugs. Alternatively you can explicitly clear the variable s to remove any existing value, just before running the FOR loop.
The dark mode beta is finally here. Change your preferences any time. Stack Overflow for Teams is a private, secure spot for you and your coworkers to find and share information. How you can read a file text or binary from a batch file? There is a way to read it in a binary mode or text mode? Also, you can parse ini files!
Type "help for" on the command prompt for more information. The expansion works only reliable, if the delayed expansion is disabled. The problem with empty lines can be solved with a trick. Prefix each line with a line number, using the findstr command, and after reading, remove the prefix.
Toggling between enable and disabled delayed expansion is neccessary for the safe working with strings, like! But the advantage is, you didn't need the delayed toggling and it's easier to store values in variables. For reading it "binary" into a hex-representation You could look at SO: converting a binary file to HEX representation using batch file.
FOR loop in Windows
This will only display the first line of text in a text file. The other way you can do it is use the following command:.
Learn more. Batch files: How to read a file? Ask Question. Asked 11 years, 6 months ago. Active 10 months ago. Viewed k times. RookieTEC9: I think you're right, it's been a while since this. Active Oldest Votes. This is a pretty complex example, parsing very specific information from a particularly formatted text file, without giving any explanation. Your example is from cmd. You should add a hint for that or copy the whole description.
Thielemann Sep 25 '19 at Under NT-style cmd. This command would quit reading a line if it found a whitespace character. It works! Direct binary reading seems therefore nearly impossible. Jeb, I asked a related question based on your solution above in stackoverflow.