Conversion of PDF to PCL in ipptransform not sending data back to ippserver. about ippsample HOT 7 OPEN

Regarding the first issue, look for errors from pdftoppm (from Poppler or Xpdf) - there are some known compatibility issues.

Regarding the PCL output, "ESC*r0B" is correct and PCL Paraphernalia is wrong - PCL 3 and 4 had an argument for the end raster graphics command while PCL 5 does not. For maximum compatibility, we need to keep the "0" argument in there.

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No it’s not pdftoppm alone. I tried different pdf files from different producers and calling pdftoppm from the command line is sending valid grafic data.
And you won’t notice the error, until you try to use ipptransform as man-in-the-middle to directly stream the result from pdftoppm to the upper level ippserver via stdout.

I think the unidirectional pipe of popen() is overwriting the opposite direction.
To call pdftoppm all the arguments are passed by command line or environment, and the result is received via stdin. The opposite direction stdout is during this time overwritten with /dev/null?
That is the main reason, why ippserver only received 4 bytes of data.

Regarding the PCL output, ESC*r0B:
I started with PCL5 and didn’t know about differences in previous versions.
Besides PCL Paraphernalia another website didn’t mention the existence of differences to earlier versions.
Sorry for the noise.

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