xref: /freebsd/lib/libc/gen/nlist.3 (revision a259b98fa211ed87bfee58c575de4e2de94ee0fa)
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28.Dd May 20, 2026
29.Dt NLIST 3
30.Os
31.Sh NAME
32.Nm nlist
33.Nd retrieve symbol table name list from an executable file
34.Sh LIBRARY
35.Lb libc
36.Sh SYNOPSIS
37.In nlist.h
38.Ft int
39.Fn nlist "const char *filename" "struct nlist *nl"
40.Sh DESCRIPTION
41The
42.Fn nlist
43function
44retrieves name list entries from
45.Xr elf 5
46sections with type
47.Dv SHT_DYNSYM
48or
49.Dv SHT_SYMTAB
50in an ELF object (for example, an executable file or shared library).
51This function is provided for compatibility with legacy applications.
52Its use is discouraged.
53.Pp
54The argument
55.Fa \&nl
56is set to reference the
57beginning of the list.
58The list is preened of binary and invalid data;
59if an entry in the
60name list is valid, the
61.Fa n_type
62and
63.Fa n_value
64for the entry are copied into the list
65referenced by
66.Fa \&nl .
67No other data is copied.
68The last entry in the list is always
69.Dv NULL .
70.Sh RETURN VALUES
71The number of invalid entries is returned if successful; otherwise,
72if the file
73.Fa filename
74does not exist or is not executable, the returned value is \-1.
75.Sh SEE ALSO
76.Xr elf 5 ,
77.Xr stab 5
78.Sh HISTORY
79A
80.Fn nlist
81function appeared in
82.At v6 .
83