Menu
Just curious, this is normal-expected behavior of ls:
user@host:~$ ls
Codes Documents Music Pictures Templates
Desktop Downloads Papers Public Videos
But when I use ls with pipe/redirection, it behave like ls -1:
user@host:~$ ls | cat
Codes
Desktop
Documents
Downloads
Music
Papers
Pictures
Public
Templates
Videos
Why? (and how to write such program that gives difference output between stdout and pipe like this?)
P.S. I also set alias l='ls -F', and this time pipe/redirection is no longer ls -1 style:
user@host:~$ l | cat
Codes/ Documents/ Music/ Pictures/ Templates/
Desktop/ Downloads/ Papers/ Public/ Videos/
Without using the alias, it does the command in ls -1 style, however:
$ ls -F | cat
Codes/
Desktop/
Documents/
Downloads/
Music/
Papers/
Pictures/
Public/
Templates/
Videos/
549
The -lh flag is the same long list format command as above, however, the file size is displayed in a human-readable format. Notice the difference between the file size outputs in the previous two screens. This option, like the standard ls command, lists all non-hidden files and directories.
How to make ls display only filenames and file sizes in output. If you want the ls command output to only contain file/directory names and their respective sizes, then you can do that using the -h option in combination with -l/-s command line option.
To show all entries for files, including those that begin with a dot (.), use the ls -a command. You can format the output in the following ways: List one entry per line, using the -l flag. List entries in multiple columns, by specifying either the -C or -x flag.
Type the ls -l command to list the contents of the directory in a table format with columns including: content permissions. number of links to the content.
You can check this line from the source:
if (format == long_format)
format = (isatty (STDOUT_FILENO) ? many_per_line : one_per_line);
It uses the isatty function to check if stdout points to a tty, and to print many_per_line if it does or one_per_line if it does not.
111
Here is how GNU ls does it (ls.c):
if (isatty (STDOUT_FILENO))
{
format = many_per_line;
}
else
{
format = one_per_line;
}
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With
