Skip site navigation (1)Skip section navigation (2)

FreeBSD Manual Pages

  
 
  

home | help
DL_ITERATE_PHDR(3)	 BSD 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 imple-
     mentation 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	dy-
		     namic linker.

     dlpi_tls_modid  The TLS index of the object.

     dlpi_tls_data   A pointer to the initialization data for the object TLS
		     segment.

     Future versions of	FreeBSD	might add more members to this structure.  To
     make it possible for programs to check whether any	new members have been
     added, the	size of	the structure is passed	as an second argument to
     callback.

     The third argument	to callback is the data	value passed to	the call to
     dl_iterate_phdr(),	allowing the callback to have a	context.

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.

BSD				October	9, 2014				   BSD

NAME | LIBRARY | SYNOPSIS | DESCRIPTION | RETURN VALUES | SEE ALSO | HISTORY

Want to link to this manual page? Use this URL:
<https://www.freebsd.org/cgi/man.cgi?query=dl_iterate_phdr&sektion=3&manpath=FreeBSD+12.0-RELEASE+and+Ports>

home | help