dlopen.3: Integrate dlvsym() discussion into main page text

Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>

diff --git a/man3/dlopen.3 b/man3/dlopen.3
index 77451cc59236987b40ec653c69ce65655426101a..a596e7f603b56e5556e3e963202c896707fc2878 100644 (file)
--- a/man3/dlopen.3
+++ b/man3/dlopen.3
@@ -47,15 +47,16 @@ programming interface to dynamic linking loader
 .sp
 .BI "int dlclose(void *" handle );
 .sp
+.B #define _GNU_SOURCE
+.br
+.B #include <dlfcn.h>
+.sp
+.BI "void *dlvsym(void *" handle ", char *" symbol ", char *" version );
+.sp
 Link with \fI\-ldl\fP.
 .SH DESCRIPTION
-The four functions
-.BR dlopen (),
-.BR dlsym (),
-.BR dlclose (),
-.BR dlerror ()
+The functions described in this page
 provide an interface to the dynamic linking loader.
-Some additional nonstandard extensions to this API are documented below.
 .SS dlerror()
 The function
 .BR dlerror ()
@@ -63,6 +64,7 @@ returns a human-readable string describing the most recent error
 that occurred from
 .BR dlopen (),
 .BR dlsym ()
+.BR dlvsym (),
 or
 .BR dlclose ()
 since the last call to
@@ -288,6 +290,12 @@ in
 can find and invoke the "real" function provided in another library
 (or for that matter, the "next" definition of the function in cases
 where there are multiple layers of preloading).
+.SS dlvsym()
+The function
+.BR dlvsym ()
+does the same as
+.BR dlsym ()
+but takes a version string as an additional argument.
 .SS dlclose()
 The function
 .BR dlclose ()
@@ -345,23 +353,6 @@ Constructor routines are executed before
 returns, and destructor routines are executed before
 .BR dlclose ()
 returns.
-.SS Glibc extension: dlvsym()
-Glibc adds the following function not described by POSIX,
-with prototype as follows:
-.sp
-.nf
-.BR "#define _GNU_SOURCE" "         /* See feature_test_macros(7) */"
-.B #include <dlfcn.h>
-.sp
-.BI "void *dlvsym(void *" handle ", char *" symbol ", char *" version );
-.fi
-.PP
-The function
-.BR dlvsym (),
-provided by glibc since version 2.1,
-does the same as
-.BR dlsym ()
-but takes a version string as an additional argument.
 .SH VERSIONS
 .BR dlopen (),
 .BR dlsym (),
@@ -378,6 +369,9 @@ POSIX.1-2001 describes
 .BR dlopen (),
 and
 .BR dlsym ().
+The
+.BR dlvsym ()
+function is a GNU extension.
 .SH NOTES
 The symbols
 .B RTLD_DEFAULT