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Re: if the file is not found the files is not found is the file not found

On Mar 4,  3:31pm, meino.cramer@xxxxxx wrote:
}      [ -f ${f}-[0-9]*.mp2 ]] && rm -f ${f}-[0-9]*.mp2

This won't work even if the files do exist, because you can't apply
a single "-f" test to the multiple files that result from the glob.

Also you've used "[" on the left but "]]" on the right, which is
mostly nonsense.  If you instead used [[ on the left then the glob
would not be expanded and the test would again fail.

On Mar 4,  3:37pm, Mikael Magnusson wrote:
} If you setopt extendedglob you can append (#qN) to the pattern

You don't even need extendedglob -- you just need bare_glob_qual, which
is on by default unless you're in sh/ksh emulation modes:

    rm -f ${f}-[0-9]*.mp2(N)

I'm sure the archives of zsh-users hold many different answers to the
question, "Given a file pattern, how do I test whether at least one
matching file exists?"  Unfortunately, there's really no way to do so
in a single operation unless you set the no_nomatch option.  [[ ]]
does not perform globbing, and the test operators such as [ -f ] are
defined to return TRUE rather than FALSE on a *missing* file name
operand, so null_glob is not sufficient.

And yet we've never added a glob qualifier to invert nomatch (nor to
invert bad_pattern) for a single glob ... however, we did invent
anonymous functions, so you can make multiple operations look like a
single operation:

if (){ setopt localoptions no_nomatch; [ -f ${f}-[0-9]*.mp2([1]) ]; }
then rm -f ${f}-[0-9]*.mp2

The "if (){ ... }" does not define a function named "if" because "if"
is a reserved word.  The ([1]) qualifier on the end of the pattern
extracts only the first matching file so that you aren't passing too
many arguments to "[ -f ... ]".

If you don't like that syntax and don't mind an extra process, you can
also do this with a subshell:

if ( setopt no_nomatch; [ -f ${f}-[0-9]*.mp2([1]) ]; )
then rm -f ${f}-[0-9]*.mp2

Woof woof.

Barton E. Schaefer

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