ssconvert problem

[bill lam <cbill lam gmail com>]

Sorry if it does not belong to this list.

I want to write a pair of filters to convert between excel and uncompressed gnumeric files,
my initial attempt is this script xls2gnm
ssconvert --import-type=Gnumeric_Excel:excel --export-type=Gnumeric_XmlIO:sax fd://0 fd://1 | zcat

it is ok if invoked in the form
xls2gnm <a.xls >b.gnumeric

but it said broken pipe when invoked as pipe
cat a.xls | xls2gnm 

to workaround, I need a temp file to hold the data
cat >/tmp/xls2gnumeric.tmp && ssconvert --import-type=Gnumeric_Excel:excel --export-type=Gnumeric_XmlIO:sax 
/tmp/xls2gnumeric.tmp fd://1 | zcat

AFAICS it is not related to zcat.  Did I miss something?

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