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25 .Dd September 16, 2022
30 .Nd extract data from the elf auxiliary vector of the current process
36 .Fn elf_aux_info "int aux" "void *buf" "int buflen"
40 function retrieves the auxiliary info vector requested in
42 The information is stored into the provided buffer if it will fit.
43 The following values, defined in
45 can be requested (corresponding buffer sizes are specified in parenthesis):
46 .Bl -tag -width AT_OSRELDATE
48 The canary value for SSP (arbitrary sized buffer, as many bytes are
49 returned as it fits into it, rest is zeroed).
51 The path of executed program
53 This may not be present if the process was initialized by
55 and the namecache no longer contains the file's name.
57 CPU / hardware feature flags
60 CPU / hardware feature flags
68 of the kernel or jail the program is running on
71 Vector of page sizes (arbitrary sized buffer, as many elements of the
73 array are returned as it fits).
78 Pointer to VDSO timehands (for library internal use,
81 Top of the user stack for main thread.
83 Limit for grow of the user stack for main thread.
86 Returns zero on success, or an error number on failure.
90 An unknown item was requested.
92 The provided buffer was not the right size for the requested item.
94 The requested item is not available.
102 Only a small subset of available auxiliary info vector items are
103 accessible with this function.
104 Some items require a "right-sized" buffer while others just require a