4 This is the Gnu Readline library, version 4.0.
6 The Readline library provides a set of functions for use by applications
7 that allow users to edit command lines as they are typed in. Both
8 Emacs and vi editing modes are available. The Readline library includes
9 additional functions to maintain a list of previously-entered command
10 lines, to recall and perhaps reedit those lines, and perform csh-like
11 history expansion on previous commands.
13 The history facilites are also placed into a separate library, the
14 History library, as part of the build process. The History library
15 may be used without Readline in applications which desire its
18 The Readline library is free software, distributed under the terms of
19 the GNU Public License, version 2. For more information, see the file
22 To build the library, try typing `./configure', then `make'. The
23 configuration process is automated, so no further intervention should
24 be necessary. Readline builds with `gcc' by default if it is
25 available. If you want to use `cc' instead, type
29 if you are using a Bourne-style shell. If you are not, the following
34 Read the file INSTALL in this directory for more information about how
35 to customize and control the build process.
37 The file rlconf.h contains C preprocessor defines that enable and disable
38 certain Readline features.
43 There are several example programs that use Readline features in the
44 examples directory. The `rl' program is of particular interest. It
45 is a command-line interface to Readline, suitable for use in shell
46 scripts in place of `read'.
51 There is skeletal support for building shared versions of the
52 Readline and History libraries. The configure script creates
53 a Makefile in the `shlib' subdirectory, and typing `make shared'
54 will cause shared versions of the Readline and History libraries
55 to be built on supported platforms.
57 Configure calls the script support/shobj-conf to test whether or
58 not shared library creation is supported and to generate the values
59 of variables that are substituted into shlib/Makefile. If you
60 try to build shared libraries on an unsupported platform, `make'
61 will display a message asking you to update support/shobj-conf for
64 If you need to update support/shobj-conf, you will need to create
65 a `stanza' for your operating system and compiler. The script uses
66 the value of host_os and ${CC} as determined by configure. For
67 instance, FreeBSD 2.2.5 with any version of gcc is identified as
70 In the stanza for your operating system-compiler pair, you will need to
71 define several variables. They are:
73 SHOBJ_CC The C compiler used to compile source files into shareable
74 object files. This is normally set to the value of ${CC}
75 by configure, and should not need to be changed.
77 SHOBJ_CFLAGS Flags to pass to the C compiler ($SHOBJ_CC) to create
78 position-independent code. If you are using gcc, this
79 should probably be set to `-fpic'.
81 SHOBJ_LD The link editor to be used to create the shared library from
82 the object files created by $SHOBJ_CC. If you are using
83 gcc, a value of `gcc' will probably work.
85 SHOBJ_LDFLAGS Flags to pass to SHOBJ_LD to enable shared object creation.
86 If you are using gcc, `-shared' may be all that is necessary.
87 These should be the flags needed for generic shared object
90 SHLIB_XLDFLAGS Additional flags to pass to SHOBJ_LD for shared library
91 creation. Many systems use the -R option to the link
92 editor to embed a path within the library for run-time
93 library searches. A reasonable value for such systems would
96 SHLIB_LIBS Any additional libraries that shared libraries should be
97 linked against when they are created.
99 SHLIB_LIBSUFF The suffix to add to `libreadline' and `libhistory' when
100 generating the filename of the shared library. Many systems
101 use `so'; HP-UX uses `sl'.
103 SHLIB_LIBVERSION The string to append to the filename to indicate the version
104 of the shared library. It should begin with $(SHLIB_LIBSUFF),
105 and possibly include version information that allows the
106 run-time loader to load the version of the shared library
107 appropriate for a particular program. Systems using shared
108 libraries similar to SunOS 4.x use major and minor library
109 version numbers; for those systems a value of
110 `$(SHLIB_LIBSUFF).$(SHLIB_MAJOR)$(SHLIB_MINOR)' is appropriate.
111 Systems based on System V Release 4 don't use minor version
112 numbers; use `$(SHLIB_LIBSUFF).$(SHLIB_MAJOR)' on those systems.
113 Other Unix versions use different schemes.
115 SHLIB_STATUS Set this to `supported' when you have defined the other
116 necessary variables. Make uses this to determine whether
117 or not shared library creation should be attempted.
119 You should look at the existing stanzas in support/shobj-conf for ideas.
121 Once you have updated support/shobj-conf, re-run configure and type
122 `make shared'. The shared libraries will be created in the shlib
125 Since shared libraries are not created on all platforms, `make install'
126 will not automatically install the shared libraries. To install them,
127 change the current directory to shlib and type `make install'. Running
128 `make install-shared' from the top-level build directory will also work.
133 The documentation for the Readline and History libraries appears in the
134 `doc' subdirectory. There are two texinfo files and a Unix-style manual
135 page describing the programming facilities available in the Readline
136 library. The texinfo files include both user and programmer's manuals.
141 Bug reports for Readline should be sent to:
145 When reporting a bug, please include the following information:
147 * the version number and release status of Readline (e.g., 4.0-release)
148 * the machine and OS that it is running on
149 * a list of the compilation flags or the contents of `config.h', if
151 * a description of the bug
152 * a recipe for recreating the bug reliably
153 * a fix for the bug if you have one!
155 If you would like to contact the Readline maintainer directly, send mail
156 to bash-maintainers@gnu.org.
158 Since Readline is developed along with bash, the bug-bash@gnu.org mailing
159 list (mirrored to the Usenet newsgroup gnu.bash.bug) often contains
160 Readline bug reports and fixes.