1LD.SO(8) Linux Programmer's Manual LD.SO(8)
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6 ld.so, ld-linux.so - dynamic linker/loader
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9 The dynamic linker can be run either indirectly by running some dynami‐
10 cally linked program or shared object (in which case no command-line
11 options to the dynamic linker can be passed and, in the ELF case, the
12 dynamic linker which is stored in the .interp section of the program is
13 executed) or directly by running:
14 /lib/ld-linux.so.* [OPTIONS] [PROGRAM [ARGUMENTS]]
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18 The programs ld.so and ld-linux.so* find and load the shared objects
19 (shared libraries) needed by a program, prepare the program to run, and
20 then run it.
21 Linux binaries require dynamic linking (linking at run time) unless the
23 -static option was given to ld(1) during compilation.
24 The program ld.so handles a.out binaries, a binary format used long
26 ago. The program ld-linux.so* (/lib/ld-linux.so.1 for libc5,
27 /lib/ld-linux.so.2 for glibc2) handles binaries that are in the more
28 modern ELF format. Both programs have the same behavior, and use the
29 same support files and programs (ldd(1), ldconfig(8), and
30 /etc/ld.so.conf).
31 When resolving shared object dependencies, the dynamic linker first in‐
33 spects each dependency string to see if it contains a slash (this can
34 occur if a shared object pathname containing slashes was specified at
35 link time). If a slash is found, then the dependency string is inter‐
36 preted as a (relative or absolute) pathname, and the shared object is
37 loaded using that pathname.
38 If a shared object dependency does not contain a slash, then it is
40 searched for in the following order:
41 o Using the directories specified in the DT_RPATH dynamic section at‐
43 tribute of the binary if present and DT_RUNPATH attribute does not
44 exist. Use of DT_RPATH is deprecated.
45 o Using the environment variable LD_LIBRARY_PATH, unless the exe‐
47 cutable is being run in secure-execution mode (see below), in which
48 case this variable is ignored.
49 o Using the directories specified in the DT_RUNPATH dynamic section
51 attribute of the binary if present. Such directories are searched
52 only to find those objects required by DT_NEEDED (direct dependen‐
53 cies) entries and do not apply to those objects' children, which
54 must themselves have their own DT_RUNPATH entries. This is unlike
55 DT_RPATH, which is applied to searches for all children in the de‐
56 pendency tree.
57 o From the cache file /etc/ld.so.cache, which contains a compiled list
59 of candidate shared objects previously found in the augmented li‐
60 brary path. If, however, the binary was linked with the -z nodeflib
61 linker option, shared objects in the default paths are skipped.
62 Shared objects installed in hardware capabi