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GELF_GETSYM(3) FreeBSD Library Functions Manual GELF_GETSYM(3)
NAME gelf_getsym, gelf_update_sym - read and update symbol information
LIBRARY ELF Access Library (libelf, -lelf)
SYNOPSIS #include <gelf.h>
GElf_Sym * gelf_getsym(Elf_Data *data, int ndx, GElf_Sym *sym);
int gelf_update_sym(Elf_Data *data, int ndx, GElf_Sym *sym);
DESCRIPTION These convenience functions are used to retrieve and update class- dependent Elf32_Sym and Elf64_Sym structures in an ELF object.
Argument data is an Elf_Data descriptor associated with a section of type SHT_SYMTAB, SHT_DYNSYM or SHT_GNU_versym. Argument ndx is the index of the symbol being retrieved or updated. The class-independent GElf_Sym structure is described in gelf(3).
Function gelf_getsym() retrieves class-dependent symbol information at index ndx in data buffer data and copies it to the destination pointed to by argument sym after translation to class-independent form.
Function gelf_update_sym() converts the class-independent symbol information pointed to by argument sym to class-dependent form, and writes it to the symbol entry at index ndx in the data buffer described by argument data. Function gelf_update_sym() signals an error if any of the values in the class-independent representation exceeds the representable limits of the target type.
RETURN VALUES Function gelf_getsym() returns the value of argument sym if successful, or NULL in case of an error. Function gelf_update_sym() returns a non- zero value if successful, or zero in case of an error.
ERRORS These functions may fail with the following errors:
[ELF_E_ARGUMENT] Arguments data or sym were NULL.
[ELF_E_ARGUMENT] Argument ndx was less than zero or larger than the number of symbols in the data descriptor.
[ELF_E_ARGUMENT] Data descriptor data was not associated with a section containing symbol information.
[ELF_E_RANGE] A value was not representable in the target type.
[ELF_E_VERSION] The Elf_Data descriptor denoted by argument data is associated with an ELF object with an unsupported version.