Hi guys,     I am using poppler to extract images from pdf, but I came across some problems. I changed the source code under poppler a little bit by adding a new interface, but I tried with a small test file, and I received an error msg in runtime as "/usr/libexec/ld- elf.so.1: ./pdf: Undefined symbol "__13PDFParserImplPci", could anyone tell me where the error comes from and what i should do to avoid it? thanks Stanley