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DL_ITERATE_PHDR(3) FreeBSD Library Functions Manual DL_ITERATE_PHDR(3)
NAME
dl_iterate_phdr - iterate over program headers
LIBRARY
For the dynamically linked binaries, the service is provided by
ld-elf.so.1(1) dynamic linker. Statically linked programs use an
implementation of dl_iterate_phdr() from libc.
SYNOPSIS
#include <link.h>
int
dl_iterate_phdr(int (*callback)(struct dl_phdr_info *, size_t, void *),
void *data);
DESCRIPTION
The dl_iterate_phdr() function iterates over all ELF objects loaded into
a process's address space, calling callback for each object, passing it
information about the object's program headers and the data argument.
The iteration is aborted when all objects are passed, or when the next
callback call returns non-zero value. The information about the program
headers is passed in a structure that is defined as:
struct dl_phdr_info {
Elf_Addr dlpi_addr;
const char *dlpi_name;
const Elf_Phdr *dlpi_phdr;
Elf_Half dlpi_phnum;
unsigned long long int dlpi_adds;
unsigned long long int dlpi_subs;
size_t dlpi_tls_modid;
void *dlpi_tls_data;
};
The members of struct dl_phdr_info have the following meaning:
dlpi_addr The base address at which the object is mapped into the
address space of the calling process.
dlpi_name The pathname of the ELF object.
dlpi_phdr A pointer to the object's program headers.
dlpi_phnum The number of program headers in the object.
dlpi_adds The counter of the object loads performed by the dynamic
linker.
dlpi_subs The counter of the object unloads performed by the
dynamic linker.
dlpi_tls_modid The TLS index of the object.
dlpi_tls_data A pointer to the calling thread' TLS data segment for
this module, if it was allocated, NULL otherwise.
Future versions of FreeBSD might add more members to this structure. To
RETURN VALUES
The dl_iterate_phdr() returns the value returned by the last callback
call executed.
SEE ALSO
ld(1), ld-elf.so.1(1), dlopen(3), elf(5)
HISTORY
The dl_iterate_phdr function first appeared in FreeBSD 7.0.
FreeBSD 14.0-RELEASE-p6 April 5, 2021 FreeBSD 14.0-RELEASE-p6