libsigc++ Reference Manual

Description

libsigc++ provides a typesafe (at compile time) callback system for standard C++. It allows you to define signals and to connect those signals to any callback function, either a global or a member function, regardless of whether it is static or virtual. It also contains adaptor classes for connection of dissimilar callbacks.

For instance, see the Signals, Functors, Slots and Adaptors.

See also the libsigc++ tutorial, the libsigc++ website, and the Signals appendix of the Programming with gtkmm book.

Features

• Compile-time typesafe callbacks (also faster than run time checks)
• Type-safety violations report the line number correctly with template names (no tracing template failures into headers)
• No compiler extensions or meta compilers required
• Proper handling of dynamic objects and signals (deleted objects will not cause crashes)
• Extendable API at any level: signal, slot, connection and trackable
• Extensions do not require alteration of basic components
• User-definable accumulators
• A variety of adaptors to change the callback signature: bind, hide, retype, and compose

Basic Usage

Include the libsigc++ header:

#include <sigc++/sigc++.h>

(You may include individual headers, such as sigc++/bind.h instead.)

If your source file is program.cc, you can compile it with:

g++ program.cc -o program `pkg-config --cflags --libs sigc++-3.0`

If your version of g++ is not C++17-compliant by default, add the -std=c++17 option.

Using Meson

If using Meson, include the following in meson.build:

sigc_dep = dependency('sigc++-3.0')
program_name = 'program'
cpp_sources = [ 'program.cc' ]
executable(program_name,
  cpp_sources,
  dependencies: sigc_dep
)

Your dependencies: keyword argument should also mention any other libraries that you need to use.

Using Autotools

Alternatively, if using autoconf, use the following in configure.ac:

PKG_CHECK_MODULES([DEPS], [sigc++-3.0])

Then use the generated DEPS_CFLAGS and DEPS_LIBS variables in the project Makefile.am files. For example:

yourprogram_CPPFLAGS = $(DEPS_CFLAGS)
yourprogram_LDADD = $(DEPS_LIBS)

Your PKG_CHECK_MODULES() call should also mention any other libraries that you need to use via pkg-config.

Using CMake

If using CMake, use the following in CMakeList.txt:

include(FindPkgConfig)
pkg_check_modules(DEPS REQUIRED sigc++-3.0)
include_directories(${DEPS_INCLUDE_DIRS})
target_link_libraries(yourprogram ${DEPS_LIBRARIES})

Your pkg_check_modules() call should also mention any other libraries that you need to use via pkg-config.