Dev:2.5/Doc/How to/Find a header button
Search for first header button in node editor. Let's start with the space (editor) type definition
1) editors/space_node/space_node.c
ED_spacetype_node() node_header_area_draw() // call to other module
2) editors/screen/area.c
ED_region_header() // list of HeaderType structs with callbacks... // where do these come from?
3) makesrna/intern./rna_ui.c
rna_Header_register() // ahh, this is called by a py script
4) release/scripts/ui/space_node.py
row.template_header() // a template?
5) makesrna/intern./rna_ui.c
RNA_def_function(srna, "template_header", "uiTemplateHeader"); // that leads us to interface code...
6) editors/interface/interface_templates.c
uiTemplateHeader() // call back to area.c
7) editors/screen/area.c
ED_area_header_standardbuttons() ED_area_header_switchbutton() uiDefIconTextButC() // Gotcha!!!