Re: Validating files and directories

[Andreas Kusalananda Kähäri]

On Sat, Nov 13, 2021 at 12:22:18AM +0000, irenezerafa via wrote:
> I am using the following commands to validate a file or directory.
> 
> if [[ ! -f "$fl" && ! -d "$fl" ]]; then
> printf '%s\n' "$fl: File or Directory does not exist"
> fi
> 
> But have noticed that I can use -e to see if there's something by that name, 
> instead of separately testing -f and -d.
> Yet I am getting confused between using -a and -e.

Why would you be confused between -a and -e?  You don't use -a here and
you never ever need to use it.

See https://unix.stackexchange.com/questions/147728

Note that you can't replace your -f and -d tests with -e if you also
care about files that are not regular files or directories (e.g.
sockets, block device files, fifos etc.)  A file that -e says exists may
be neither a regular file nor a directory.

You could possibly say

        if [[ -e "$fl" ]]; then
                if [[ ! -f "$fl" ]] && [[ ! -d "$fl" ]]; then
                        printf '%s exists but is neither directory nor 
regular\n' "$fl"
                else
                        printf '%s exists and is directory or regular\n' "$fl"
                fi
        else
                printf '%s does not exist\n' "$fl"
        fi

The -e test is not a file-type test, while both -f and -d are.

-- 
Andreas (Kusalananda) Kähäri
SciLifeLab, NBIS, ICM
Uppsala University, Sweden

.