I don't know about your pdflatex, but all versions that I've used so far (miktex, texlive, xelatex) automatically wrote a .log file, which contains a transcript of the latex output.

So system("pdlatex $other_options $filename.tex >/dev/null 2>&1"); should do, and then examine $filename.pdf.

By the way File::Temp offers a safer and better way to generate temporary files (and file names).