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From: D Gowers <finticemo@gmail.com>
To: zsh-workers@zsh.org
Subject: expr length "$val" returns the wrong length for values containing NULL (\\0)
Date: Thu, 10 Dec 2015 12:22:16 +1030	[thread overview]
Message-ID: <CAMf8R07=5LKcg3f6VaFDKi9TBt855=t9J7tzqhDjQihB2ftEmg@mail.gmail.com> (raw)

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Test case:

v=$(printf foo\\0bar);expr length "$v";expr length $v

alternatively:

v=foo$'\0'bar;expr length "$v";expr length $v

In zsh, the values returned are  3 and 3.
In dash and zsh, the values returned are 6 and 6.

Both of those results are wrong, AFAICS (foo$'0'bar is 7 characters long).
But the zsh result is more severely wrong. I could understand the bash/dash
result, at least,  as 'NULL characters are not counted towards length'.

In any case, it is easily demonstrated that the string is not 3 characters
long, by running 'echo "$V"' or 'print "$v"' or 'echo ${#v}'

`zsh --version` = 'zsh 5.2 (x86_64-unknown-linux-gnu)'

             reply	other threads:[~2015-12-10  1:52 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-12-10  1:52 D Gowers [this message]
2015-12-10  3:56 ` Nikolay Aleksandrovich Pavlov (ZyX)
2015-12-10  4:18   ` D Gowers
2015-12-10  4:29     ` Nikolay Aleksandrovich Pavlov (ZyX)
2015-12-10  5:00       ` D Gowers
2015-12-10  9:37         ` Peter Stephenson
2015-12-10 17:47           ` Nikolay Aleksandrovich Pavlov (ZyX)

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