HP-UX Reference (11i v3 07/02) - 5 Miscellaneous Topics (vol 9)

dld.so(5) dld.so(5)

(Itanium(R)-based System Only)

When using the explicit load facilities of the dynamic loader, these types of errors are not considered fatal.

Consult shl_load(3X), dlclose(3C), dlget(3C), dlgetname(3C), dlmodinfo(3C), dlopen(3C), and dlsym(3C) for

more information. To see error messages, use the

dlerror() routine. This routine prints the last error

message recorded by the dynamic loader.

WARNINGS

The startup cost of the dynamic loader is signiﬁcant, even with deferred binding, and can cause severe per-

formance degradation in processes dominated by startup costs (such as simple ‘‘hello world’’ programs). In

addition, position-independent code is usually slower than normal code, so performance of a program may

be adversely affected by the presence of PIC in shared libraries. However, the advantages of decreased

disk space usage and decreased memory requirements for executables should outweigh these concerns in

most cases.

There are rare cases where the behavior of a program differs when using shared libraries as opposed to

archive libraries. This happens primarily when relying on undocumented and unsupported features of the

compilers, assembler, and linker. See the

+help option to ld(1) or the HP-UX Linker and Libraries User’s

Guide for more details.

The library developer is entirely responsible for version control and must be thorough in identifying incom-

patible changes to library interfaces. Otherwise, programs may malfunction unexpectedly with later ver-

sions of the library. There is little an application user can do if version control is not handled properly by

the library developer. The application developer can usually resolve problems by modifying the source code

to use the new interfaces then recompiling and relinking against the new libraries.

By default, most warnings are not reported by the dynamic loader. If you wish to see all error messages,

set the environment variable

DLD_VERBOSE_ERR

to true.

AUTHOR

The

/usr/lib/hpux64/dld.so

and /usr/lib/hpux32/dld.so shared libraries were developed

by HP.