Re: Validating files and directories

[Alex fxmbsw7 Ratchev]

and sockets and fifos
but nice one..

On Sat, Nov 13, 2021, 10:33 Andreas Kusalananda Kähäri <
andreas.kahari@abc.se> wrote:

> On Sat, Nov 13, 2021 at 10:06:01AM +0100, Kusalananda Kähäri wrote:
> > 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' "$fl"
> >       fi
> >
> > The -e test is not a file-type test, while both -f and -d are.
>
> Sorry, I forgot about symbolic links...
>
>         if [[ -e "$fl" ]]; then
>                 if [[ -f "$fl" ]] || [[ -d "$fl" ]]; then
>                         printf '%s exists and is ' "$fl"
>                         if [[ -h "$fl" ]]; then
>                                 printf 'a symbolic link to '
>                         fi
>                         printf 'a directory or regular file\n'
>                 else
>                         printf '%s exists but is ' "$fl"
>                         if [[ -h "$fl" ]]; then
>                                 printf 'a symbolic link to '
>                         fi
>                         printf 'neither directory nor regular file\n'
>                 fi
>         elif [[ -h "$fl" ]]; then
>                 printf '%s is a broken symbolic link\n' "$fl"
>         else
>                 printf '%s does not exist\n' "$fl"
>         fi
>
>
> --
> Andreas (Kusalananda) Kähäri
> SciLifeLab, NBIS, ICM
> Uppsala University, Sweden
>
> .
>
>