how to avoid overlapping edge and node when using graphviz?

As title,I want to draw an image of ELF file format.The ELF Header has offset of program headers table and section headers table,so I want to use two arrows po开发者_运维知识库inter to point out the relationship.But the edges overlap the node(record) even after I have overlap=false and splines=true set.I have search for a while,but my situation is that the arrows somewhat point to parts of itself.

Following is the dot file I am using to generate the png file.

digraph g {
//margin="1"
overlap='scale'
graph [rankdir="LR"]

"ELF File" [
label="<f0> ELF Header\n e_shoff=0x118| <f1> Program Headers Table | <f2> .text | <f3> .data | <f4> .rodata| <f5> .comment | <f6> .shstrtab | <f8> .symtab | <f9> .rel.text | <f7> Section Table"
shape="record"
];

"ELF File":f0 -> "ELF File":f1 [label="e_phoffset"]
"ELF File":f0 -> "ELF File":f7 [label="e_shoff"]
}

One possible solution is to use "east" node ports on one of the edges, so that this edge appears on opposite side of the record. You do this by appending :e to the node name. For example:

"ELF File":f0:e -> "ELF File":f7:e [label="e_shoff"]