/usr/share/acl2-7.1/books/projects/concurrent-programs/ is in acl2-books 7.1-1.
This file is owned by root:root, with mode 0o755.
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/usr/share/acl2-7.1/books/projects/concurrent-programs/bakery/
/usr/share/acl2-7.1/books/projects/concurrent-programs/bakery/apply-total-order.o
/usr/share/acl2-7.1/books/projects/concurrent-programs/bakery/fairenv.o
/usr/share/acl2-7.1/books/projects/concurrent-programs/bakery/final-theorems.o
/usr/share/acl2-7.1/books/projects/concurrent-programs/bakery/initial-state.o
/usr/share/acl2-7.1/books/projects/concurrent-programs/bakery/inv-persists.o
/usr/share/acl2-7.1/books/projects/concurrent-programs/bakery/inv-sufficient.o
/usr/share/acl2-7.1/books/projects/concurrent-programs/bakery/labels.o
/usr/share/acl2-7.1/books/projects/concurrent-programs/bakery/lexicographic-pos.o
/usr/share/acl2-7.1/books/projects/concurrent-programs/bakery/lexicographic.o
/usr/share/acl2-7.1/books/projects/concurrent-programs/bakery/measures.o
/usr/share/acl2-7.1/books/projects/concurrent-programs/bakery/pos-temp.o
/usr/share/acl2-7.1/books/projects/concurrent-programs/bakery/programs.o
/usr/share/acl2-7.1/books/projects/concurrent-programs/bakery/properties-of-sets.o
/usr/share/acl2-7.1/books/projects/concurrent-programs/bakery/properties.o
/usr/share/acl2-7.1/books/projects/concurrent-programs/bakery/records.o
/usr/share/acl2-7.1/books/projects/concurrent-programs/bakery/stutter1-match.o
/usr/share/acl2-7.1/books/projects/concurrent-programs/bakery/stutter2.o
/usr/share/acl2-7.1/books/projects/concurrent-programs/bakery/variables.o
/usr/share/acl2-7.1/books/projects/concurrent-programs/german-protocol/
/usr/share/acl2-7.1/books/projects/concurrent-programs/german-protocol/german.o