猛击。 将grep的输出重定向到文件中

Question

I have a basic bash script that i want to use to create a list of directories inside a file. The issue is that when i type the following command on the terminal it works fine but when used inside a function it does not

function Create_file_dirs()
{ 
    ls | grep / > dirs.txt
    cat dirs.txt #used for debugging
}

This function is inside a script and i'm running it by calling the script. ./script.sh

`

The command ls | grep / > dirs.txt ls | grep / > dirs.txt works great on the terminal window and produces a file listing directories line by line, but doesn't do anything when used inside a function and i can't figure out why. Thanks

Answer 1

ls without options does not produce slashes, so grep doesn't find anything. You can easily reproduce it on the command line by, say,

comand ls|grep /

Answer 2

My thanks to William Pursell for his answer and to everyone who contributed.

The answer came from a comment made by William Pursell. The working function is:

    create_file_dirs()
{ 
    ls -F | grep / >./dirs.txt
    cat dirs.txt
}

The issue was,that when i was running the ls command on the terminal i could see a slash / after a directories name and running the command on the terminal actually produced the desired result.

ls | grep / > ./dirs.txt

It seems though running ls through a script doesn't produce a slash / after a directories name that is why i had to add them -F option to resolve this issue.

The way i tested it out was with this simple function inside a script and run the script. The result didn't have slashes.

test_dirs(){
    ls | cat
}