USELIB(2) Linux Programmer's Manual USELIB(2)
NAME
uselib - load shared library
SYNOPSIS
#include <unistd.h>
int uselib(const char *library);
Note: No declaration of this system call is provided in glibc headers;
see NOTES.
DESCRIPTION
The system call uselib() serves to load a shared library to be used by
the calling process. It is given a pathname. The address where to
load is found in the library itself. The library can have any recog-
nized binary format.
RETURN VALUE
On success, zero is returned. On error, -1 is returned, and errno is
set appropriately.
ERRORS
In addition to all of the error codes returned by open(2) and mmap(2),
the following may also be returned:
EACCES The library specified by library does not have read or execute
permission, or the caller does not have search permission for
one of the directories in the path prefix. (See also path_reso-
lution(7).)
ENFILE The system-wide limit on the total number of open files has been
reached.
ENOEXEC
The file specified by library is not an executable of a known
type; for example, it does not have the correct magic numbers.
CONFORMING TO
uselib() is Linux-specific, and should not be used in programs intended
to be portable.
NOTES
This obsolete system call is not supported by glibc. No declaration is
provided in glibc headers, but, through a quirk of history, glibc ver-
sions before 2.23 did export an ABI for this system call. Therefore,
in order to employ this system call, it was sufficient to manually de-
clare the interface in your code; alternatively, you could invoke the
system call using syscall(2).
In ancient libc versions (before glibc 2.0), uselib() was used to load
the shared libraries with names found in an array of names in the bi-
nary.
Since Linux 3.15, this system call is available only when the kernel is
configured with the CONFIG_USELIB option.
SEE ALSO
ar(1), gcc(1), ld(1), ldd(1), mmap(2), open(2), dlopen(3), capabili-
ties(7), ld.so(8)
COLOPHON
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