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Re: 1.7.35: .sh script in dos format does not work.

On 04/22/2015 03:24 PM, cyg Simple wrote:
>> From: Eric Blake
>> It looks like something is going wrong with lseek() mixed with text-mode
>> mounts.
> I thought lseek was reserved for binary only channels due to the loss of character count because of the CRLF to LF translation.

[you may want to teach your mailer to wrap long lines]

lseek works on files opened in text mode - BUT it only works to the
underlying offset in the file.  You are correct that if you read() 500
bytes, and then try to seek relative to current offset backwards by 100
bytes, that you have to be careful of whether you meant 100 bytes of
text read (but possibly more than 100 bytes when you include \r), or 100
bytes of offset (but possibly less than 100 bytes read because \r was

What I haven't yet determined is if the bug lies in bash, for using
lseek() with the wrong numbers on a text mode file, or in cygwin itself,
for not properly handling file repositioning of stdin after flush()
prior to fork(), when stdin is in text mode.

Eric Blake   eblake redhat com    +1-919-301-3266
Libvirt virtualization library

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