[tex4ht] Can??t find/open file ??xxx.dvi?? or ??xxx.lg??

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hello, I got this error when i try to use tex4ebook to convert arxiv paper 
source to epub.
I found a solution in https://www.tug.org/tex4ht/doc/mn3.html, which sugget 
install htcmd.c. But I could not find htcmd, could you give me some advice? by 
the way my system is ubuntu14.
Morever, when i use tex4ebook to convert some sigle tex file, it worked. And it 
didn't produce dvi too.