uselib(2) — Linux manual page


USELIB(2)               Linux Programmer's Manual              USELIB(2)

NAME         top

       uselib - load shared library

SYNOPSIS         top

       #include <unistd.h>

       int uselib(const char *library);

       Note: No declaration of this system call is provided in glibc
       headers; see NOTES.

DESCRIPTION         top

       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 recognized binary format.

RETURN VALUE         top

       On success, zero is returned.  On error, -1 is returned, and
       errno is set to indicate the error.

ERRORS         top

       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_resolution(7).)

       ENFILE The system-wide limit on the total number of open files
              has been reached.

              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         top

       uselib() is Linux-specific, and should not be used in programs
       intended to be portable.

NOTES         top

       This obsolete system call is not supported by glibc.  No
       declaration is provided in glibc headers, but, through a quirk of
       history, glibc versions before 2.23 did export an ABI for this
       system call.  Therefore, in order to employ this system call, it
       was sufficient to manually declare 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 binary.

       Since Linux 3.15, this system call is available only when the
       kernel is configured with the CONFIG_USELIB option.

SEE ALSO         top

       ar(1), gcc(1), ld(1), ldd(1), mmap(2), open(2), dlopen(3),

COLOPHON         top

       This page is part of release 5.13 of the Linux man-pages project.
       A description of the project, information about reporting bugs,
       and the latest version of this page, can be found at

Linux                          2021-03-22                      USELIB(2)

Pages that refer to this page: fanotify_mark(2)syscalls(2)