sjmulder / dltest

Test for library presence.

dltest

Test for library presence.

dltest [-aq] library [...]

Description

Attempt to open the given libraries using dlopen_preflight if available, or dlopen otherwise.

Names of successfully loaded libraries are printed to standard output, loading errors to standard error, and success is returned if any of the loads was successful.

Options:

-a: Only return success if all of the given libraries could be loaded.

-q: Don't print loaded libraries or errors.

Especially useful on macOS 11 and up which doesn't include regular shared library files but only a precompiled shared library cache.

Exits 0 on success or 1 on failure (see description), or 64 for bad usage.

Examples

See if some libraries are available:

$ dltest libcurses.dylib libtermcap.dylib libterminfo.dylib
libcurses.dylib
libtermcap.dylib
dlopen_preflight(libterminfo.dylib): image not found

To see if we have all of them using -a:

$ dltest -aq libcurses.dylib libtermcap.dylib libterminfo.dylib \
    && echo YES || echo NO
NO

Installation

Should work on any Unix, including Linux and macOS.

1. Install C build tools if necessary.
   • Debian or Ubuntu: apt install build-essential
   • macOS: install the Xcode Command Line Tools.
2. Download and extract the source.
3. Build with make.
4. Install with make install as root (e.g. sudo make install).

See the Makefile for more details.

Author

Sijmen J. Mulder ([e-mail])