GNU Info

(tar.info)short create

---

Next: create dir Prev: create verbose Up: create

---

Enter node , (file) or (file)node

Short Forms with `create'
-------------------------

   As we said before, the `--create' (`-c') operation is one of the most
basic uses of `tar', and you will use it countless times.  Eventually,
you will probably want to use abbreviated (or "short") forms of
options.  A full discussion of the three different forms that options
can take appears in Note: Styles; for now, here is what the previous
example (including the `--verbose' (`-v') option) looks like using
short option forms:

     $ tar -cvf collection.tar blues folk jazz
     blues
     folk
     jazz

As you can see, the system responds the same no matter whether you use
long or short option forms.

   One difference between using short and long option forms is that,
although the exact placement of arguments following options is no more
specific when using short forms, it is easier to become confused and
make a mistake when using short forms.  For example, suppose you
attempted the above example in the following way:

     $ tar -cfv collection.tar blues folk jazz

In this case, `tar' will make an archive file called `v', containing
the files `blues', `folk', and `jazz', because the `v' is the closest
"file name" to the `-f' option, and is thus taken to be the chosen
archive file name.  `tar' will try to add a file called
`collection.tar' to the `v' archive file; if the file `collection.tar'
did not already exist, `tar' will report an error indicating that this
file does not exist.  If the file `collection.tar' does already exist
(e.g., from a previous command you may have run), then `tar' will add
this file to the archive.  Because the `-v' option did not get
registered, `tar' will not run under `verbose' mode, and will not
report its progress.

   The end result is that you may be quite confused about what happened,
and possibly overwrite a file.  To illustrate this further, we will show
you how an example we showed previously would look using short forms.

   This example,

     $ tar blues --create folk --file=collection.tar jazz

is confusing as it is.  When shown using short forms, however, it
becomes much more so:

     $ tar blues -c folk -f collection.tar jazz

It would be very easy to put the wrong string of characters immediately
following the `-f', but doing that could sacrifice valuable data.

   For this reason, we recommend that you pay very careful attention to
the order of options and placement of file and archive names,
especially when using short option forms.  Not having the option name
written out mnemonically can affect how well you remember which option
does what, and therefore where different names have to be placed.
(Placing options in an unusual order can also cause `tar' to report an
error if you have set the shell environment variable `POSIXLY_CORRECT';
Note: posix compliance for more information on this.)