Read filenames using for loop in shell script

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In my folder, filenames are like this:

A00001
A00002
.
.
.
A08525

I want to add this file name as an argument:

max = 8525
for i in `seq 2 $max`
do
    python script.py -r filename 
done

I tried like this:

max = 8525
for i in `seq 2 $max`
do
    python script.py -r "A0000$i" #But this work for 1-9 like wise for A000 it will work for 100-999
done

I can not do

for file in A*; 
do 
    echo "$file"; done
done

Because the folder has the same file with three different extensions, like A0000.txt, A0000.pdf, A0000.png, and I want to input only A0000 as an argument.

How can I write the for loop so that I can read all filenames?

Most(?) versions of seq will support outputting 0-padded values.

max=8525
for i in $(seq -w 2 $max); do
  python script.py -r "A$i"
done

Alternately, you can simply loop over the existing files and strip the extension.

for f in A*.txt; do
  f=${f%.txt}
  python script.py -r "$f"
done    

Bash Shell Loop Over Set of Files, Sample Shell Script To Loop Through All Files Now you can use the while loop as follows to read and process each by one by one:� The read command in the While loop reads a line from standard input and saves the contents to the variable line. In this case, the -r option guarantees that the content read in is the original content, meaning that the backslash escape will not occur. Enter the redirect operator < file to open and read the file file, and then use it as standard input for the read command.

You can use printf to pad a number with leading zeros.

for ((i=1; i<=8525; ++i)); do
    printf -v filename "A%05i" "$i"
    python script.py -r "filename"
done

Of course, if the base filenames already exist, you can do

for f in A[0-9][0-9][0-9][0-9][0-9].png; do
    filename=${f%.png}
    python script.py -r "$filename"
done

which neatly avoids hardcoding the upper limit.

Loop over list of files, Shell loop through files - Examples. if a line may include spaces better use a while loop: cat filelist.txt | while read LINE; do echo "${LINE}"; done. loop over filenames, but remove file extension, see → basename string split. loop over filenames, but remove file extension and path prefix. Read filenames using for loop in shell script. Ask Question Asked 9 months ago. Active 9 months ago. Viewed 39 times 0. In my folder, filenames are like this:

for file in $(find /path/to/your/files -type f -name "A?????");do python script.py -r "$file"; done

How to write a loop in Bash, Automatically perform a set of actions on multiple files with for loops and find commands. A common reason people want to learn the Unix shell is to unlock the power of batch For advanced for loop topics, read on. The for loop using ranges or counting. The for loop can be set using the numerical range. The range is specified by a beginning and ending number. The for loop executes a sequence of commands for each member in a list of items. A representative example in BASH is as follows to display multiplication table with for loop (multiplication.sh):

Loop through a folder and list files, Use basename to strip the leading path off of the files: for file in sample/*; do echo "$(basename "$file")" done. Though why not: ( cd sample; ls ). whereas the script is more flexible and inside loop can do any operations with filenames.. no, you have to fix it by hand. If we like to delete the files, you will replace your echo with an rm, and I will replace ls -a with rm. rm is just simple operation. What if some consecutive operations , use of | would not be efficient in such cases.

Command-line Basics: How to Loop Through Files in a Directory , Learn how to loop through the files in a directory and run commands against them using shell scripting for loops. cat filelist.txt | while read LINE; do echo "${LINE}"; done loop over filenames, but remove file extension , see → basename string split for f in Data/*.txt; do FILENAME= ${ f%%.* } ; echo ${FILENAME}; done;

How to loop through file names returned by find?, Plus, this command will work even if a file name is returned with whitespace in it. can read the output of find into a Bash array using the following command: For loop in shell script works the following way whenever shell sees the keyword for it knows that it needs to repeat a set of commands once for every item in a list. Each time when iteration runs an item in the list is assigned to the variable var and the var is processed through the list of commands present in the loop between doing and done

Comments
  • How about for file in A*; do echo "$file"; done?
  • @MichaWiedenmann: Thanks, this I though but actually folder has same file with three different extensions. like A0000.txt A0000.pdf A0000.png and I want to input only A0000 without extension
  • max=8525; spaces are not allowed.
  • Possible duplicate of stackoverflow.com/questions/54844645/…
  • Your examples have five digits but then a lot of the rest of the discussion shows four. Which is it?
  • I want to use it without file extention, I directly used f but that also comes with file extension. Any clue?
  • f=${f%.txt} should remove the extension.
  • If you want only four digits after A, obviously use "A%04i" for the format string instead.
  • please check my update question. Thanks for your answer
  • I tried for file in $(find training2017/ -type f -name "A?????"); do #python script.py -r echo "$file"; done but it did not print anything
  • @Jhon how many digits are after "A" in the filenames ? , if it's 4, just change the file name pattern to "A????"
  • Why did you put training2017/ in the find command? Nothing else here mentions a subdirectory like that.
  • @tripleee: All files are in training2017 directory