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VL_LIB_READLINE
1.1 0.5.57 : Installed_Packages
Ville Laurikari <vl@iki.fi>
Searches for a readline compatible library. If found, defines `HAVE_LIBREADLINE'. If the found library has the `add_history' function, sets also `HAVE_READLINE_HISTORY'. Also checks for the locations of the necessary include files and sets `HAVE_READLINE_H' or `HAVE_READLINE_READLINE_H' and `HAVE_READLINE_HISTORY_H' or 'HAVE_HISTORY_H' if the corresponding include files exists.
The libraries that may be readline compatible are `libedit', `libeditline' and `libreadline'. Sometimes we need to link a termcap library for readline to work, this macro tests these cases too by trying to link with `libtermcap', `libcurses' or `libncurses' before giving up.
Here is an example of how to use the information provided by this macro to perform the necessary includes or declarations in a C file:
#ifdef HAVE_LIBREADLINE
# if defined(HAVE_READLINE_READLINE_H)
# include <readline/readline.h>
# elif defined(HAVE_READLINE_H)
# include <readline.h>
# else /* !defined(HAVE_READLINE_H) */
extern char *readline ();
# endif /* !defined(HAVE_READLINE_H) */
char *cmdline = NULL;
#else /* !defined(HAVE_READLINE_READLINE_H) */
/* no readline */
#endif /* HAVE_LIBREADLINE */
#ifdef HAVE_READLINE_HISTORY
# if defined(HAVE_READLINE_HISTORY_H)
# include <readline/history.h>
# elif defined(HAVE_HISTORY_H)
# include <history.h>
# else /* !defined(HAVE_HISTORY_H) */
extern void add_history ();
extern int write_history ();
extern int read_history ();
# endif /* defined(HAVE_READLINE_HISTORY_H) */
/* no history */
#endif /* HAVE_READLINE_HISTORY */
AC_DEFUN([VL_LIB_READLINE], [
AC_CACHE_CHECK([for a readline compatible library],
vl_cv_lib_readline, [
ORIG_LIBS="$LIBS"
for readline_lib in readline edit editline; do
for termcap_lib in "" termcap curses ncurses; do
if test -z "$termcap_lib"; then
TRY_LIB="-l$readline_lib"
else
TRY_LIB="-l$readline_lib -l$termcap_lib"
fi
LIBS="$ORIG_LIBS $TRY_LIB"
AC_TRY_LINK_FUNC(readline, vl_cv_lib_readline="$TRY_LIB")
if test -n "$vl_cv_lib_readline"; then
break
fi
done
if test -n "$vl_cv_lib_readline"; then
break
fi
done
if test -z "$vl_cv_lib_readline"; then
vl_cv_lib_readline="no"
LIBS="$ORIG_LIBS"
fi
])
if test "$vl_cv_lib_readline" != "no"; then
AC_DEFINE(HAVE_LIBREADLINE, 1,
[Define if you have a readline compatible library])
AC_CHECK_HEADERS(readline.h readline/readline.h)
AC_CACHE_CHECK([whether readline supports history],
vl_cv_lib_readline_history, [
vl_cv_lib_readline_history="no"
AC_TRY_LINK_FUNC(add_history, vl_cv_lib_readline_history="yes")
])
if test "$vl_cv_lib_readline_history" = "yes"; then
AC_DEFINE(HAVE_READLINE_HISTORY, 1,
[Define if your readline library has \`add_history'])
AC_CHECK_HEADERS(history.h readline/history.h)
fi
fi
])dnl