gspell provides a flexible API to add spell checking to a GTK application. See the gspell home page.
The pkg-config name of the gspell library is: gspell-1
To compile a program that uses gspell, you can for example use the following command:
$ gcc hello.c `pkg-config --cflags --libs gspell-1` -o hello
See the gspell_text_view_basic_setup()
convenience function to quickly enable inline spell checking in a
GtkTextView widget.
See the gspell_entry_basic_setup()
convenience function to quickly enable inline spell checking in a
GtkEntry widget.