1 GNU C Library NEWS -- history of user-visible changes. 2 January 1996
3 Copyright (C) 1992, 93, 94, 95, 96 Free Software Foundation, Inc.
4 See the end for copying conditions.
6 Please send GNU C library bug reports to bug-glibc@prep.ai.mit.edu.
10 * The library has changed from using GNU ld symbol aliases to using weak
11 symbols where available. The ELF object file format supports weak
12 symbols; GNU ld also supports weak symbols in the a.out format. (There
13 is also now support for other GNU ld extensions in ELF. Use the
14 `--with-elf' option to configure to indicate you have ELF, and
15 `--with-gnu-ld' if using GNU ld.) This change resulted in the deletion
16 of many files which contained only symbol aliases, reducing the size of
17 the source and the compiled library; many other files were renamed to
18 less cryptic names previously occupied by the symbol alias files.
19 There is a new header file <elf.h> and new library `-lelf' for
20 programs which operate on files in the ELF format.
22 * Converted to Autoconf version 2, so `configure' has more options.
23 Run `configure --help' to see the details.
25 * The library can now be configured to build profiling, highly-optimized
26 (but undebuggable), and/or shared libraries (ELF with GNU ld only). The
27 `--enable-profile', `--enable-omitfp', and `--enable-shared' options to
28 `configure' enable building these extra libraries. The shared library is
29 built by default when using both ELF and GNU ld. When shared libraries
30 are enabled, the new library `-ldl' is available for arbitrary run-time
31 loading of shared objects; its interface is defined in <dlfcn.h>. The
32 new header file <link.h> gives access to the internals of the run-time
33 dynamic linker, `ld.so'.
35 * The C library now provides the run-time support code for profiling
36 executables compiled with `-pg'. Programs can control the profiling code
37 through the interface in <sys/gmon.h>. The profiling code was adapted
40 * The new functions `strtoq' and `strtouq' parse integer values from
41 strings, like `strtol' and `strtoul', but they return `long long int' and
42 `unsigned long long int' values, respectively (64-bit quantities).
44 * The new functions `strtof' and `strtold' parse floating-point values from
45 strings, like `strtod', but they return `float' and `long double' values,
46 respectively (on some machines `double' and `long double' are the same).
48 * Ulrich Drepper has contributed new implementations of the floating-point
49 printing and reading code used in the `printf' family of functions and
50 `strtod', `strtof', and `strtold'. These new functions are perfectly
51 accurate, and much faster than the old ones.
53 * The new header <langinfo.h> defines an interface for accessing
54 various locale-dependent data (using the locale chosen with `setlocale').
56 * You can now use positional parameter specifications in format strings
57 for the `printf' and `scanf' families of functions. For example,
58 `printf ("Number %2$d, Mr %1$s\n", "Jones", 6);'' prints
59 ``Number 6, Mr Jones''. This is mainly useful when providing different
60 format strings for different languages, whose grammars may dictate
61 different orderings of the values being printed. To support this
62 feature, the interface for `register_printf_handler' has changed; see
63 the header file <printf.h> for details.
65 * The `printf' and `scanf' families of functions now understand a new
66 formatting flag for numeric conversions: the ' flag (e.g. %'d or %'f) says
67 to group numbers as indicated by the locale; for `scanf' and friends, this
68 says to accept as valid only a number with all the proper grouping
69 separators in the right places. In the default "C" locale, numbers are
70 not grouped; but locales for specific countries will define the usual
71 conventions (i.e. separate thousands with `,' in the US locale).
73 * The pgrp functions have been regularized, slightly incompatibly but much
74 less confusingly. The core functions are now `getpgid' and `setpgid',
75 which take arguments for the PID to operate on; the POSIX.1 `getpgrp' (no
76 argument) and BSD `setpgrp' (identical to `setpgid') functions are
77 provided for compatibility. There is no longer an incompatible `getpgrp'
78 with an argument declared under _BSD_SOURCE; no BSD code uses it.
80 * The new header file <fts.h> and suite of functions simplify programs that
81 operate on directory trees. This code comes from 4.4 BSD.
83 * The resolver code has been updated from the BIND 4.9.3 release.
85 * The new function `malloc_find_object_address' finds the starting address
86 of a malloc'd block, given any address within the block. This can be
89 * There is a new malloc debugging hook `__memalign_hook'.
91 * There are new typedefs `ushort' for `unsigned short int' and `uint' for
92 `unsigned int' in <sys/types.h>. These are for compatibility only and
93 their use is discouraged.
95 * The `-lmcheck' library to enable standard malloc debugging hooks is now
96 done differently, so that it works even without GNU ld.
98 * New function `euidaccess' checks allowed access to a file like `access',
99 but using the effective IDs instead of the real IDs.
101 * The time zone data files have been updated for the latest and greatest
102 local time conventions of the countries of the world.
104 * The new function `dirfd' extracts the file descriptor used by a DIR stream;
107 * The new functions `ecvt', `fcvt', and `gcvt' provide an obsolete interface
108 for formatting floating-point numbers. They are provided only for
109 compatibility; new programs should use `sprintf' instead.
111 * The new auxiliary library `-lutil' from 4.4 BSD contains various
112 functions for maintaining the login-record files (primarily of use to
113 system programs such as `login'), and convenient functions for
114 allocating and initializing a pseudo-terminal (pty) device.
116 * Ulrich Drepper has contributed new support for System V style
117 shared memory and IPC on systems that support it.
119 * Ulrich Drepper has contributed several miscellaneous new functions found
120 in System V: The `hsearch' family of functions provide an effective
121 implementation of hash tables; `a64l' and `l64a' provide a very simple
122 binary to ASCII mapping; `drand48' and friends provide a 48-bit random
125 * Ulrich Drepper has contributed new reentrant counterparts for the
126 `random' and `hsearch' families of functions; `random_r', `hsearch_r', etc.
128 * Ulrich Drepper has contributed new, highly-optimized versions of several
129 string functions for the i486/Pentium family of processors.
131 * Ulrich Drepper has updated the Linux-specific code, based largely
132 on work done in Hongjiu Lu's version of GNU libc for Linux.
133 The GNU library now supports Linux versions 1.3.29 and later,
134 using the ELF object file format (i[345]86-*-linux).
136 * Ulrich Drepper has contributed a new set of message catalog functions to
137 support multiple languages, for use with his new package GNU gettext.
139 * New header file <values.h> gives SVID-compatible names for <limits.h>
142 * Various new macros, declarations, and small header files for compatibility
145 * New function `group_member' is a convenient way to check if a process has
146 a given effective group ID.
148 * When using GCC 2.7 and later, the socket functions are now declared in a
149 special way so that passing an argument of type `struct sockaddr_in *',
150 `struct sockaddr_ns *', or `struct sockaddr_un *' instead of the generic
151 `struct sockaddr *' type, does not generate a type-clash warning.
153 * New function `error' declared in header file <error.h> is a convenient
154 function for printing error messages and optionally exitting; this is the
155 canonical function used in GNU programs. The new functions `err', `warn',
156 and friends in header file <err.h> are the canonical 4.4 BSD interface for
157 doing the same thing.
159 * The <glob.h> interface has several new flags from 4.4 BSD that extend the
160 POSIX.2 `glob' function to do ~ and {...} expansion.
162 * New function `unsetenv' complements `setenv' for compatibility with 4.4 BSD.
164 * New function `getsid' returns session ID number on systems that support it.
166 * The 4.4 BSD `db' library has been incorporated into the GNU C library.
167 New header files <db.h> and <mpool.h> provide a rich set of functions for
168 several types of simple databases stored in memory and in files, and
169 <ndbm.h> is an old `ndbm'-compatbile interface using the `db' functions.
173 * For cross-compilation you should now set `BUILD_CC' instead of `HOST_CC'.
175 * New header file <fstab.h> and new functions `getfsspec', `getfsent' and
176 friends, for parsing /etc/fstab. This code comes from 4.4 BSD.
178 * The new function `daemon' from 4.4 BSD is useful for server programs that
179 want to put themselves in the background.
181 * Joel Sherrill has contributed support for several standalone boards that
182 run without an operating system.
184 * `printf', `scanf' and friends now accept a `q' type modifier for long
185 long int as well as `ll'. Formats using these might be `%qu' or `%lld'.
187 * All of the code taken from BSD (notably most of the math and networking
188 routines) has been updated from the BSD 4.4-Lite release.
190 * The resolver code has been updated from the BIND-4.9.3-BETA9 release.
192 * The new functions `getdomainname' and `setdomainname' fetch or change the
193 YP/NIS domain name. These are system calls which exist on systems which
196 * The time zone data files have been updated for the latest international
199 * The SunRPC programs `portmap' and `rpcinfo' are now installed in
200 $(sbindir) (usually /usr/local/sbin) instead of $(bindir).
204 * The C library now includes support for Sun RPC, from Sun's free
205 RPCSRC-4.0 distribution. The `portmap', `rpcinfo', and `rpcgen' programs
206 are included. (There is still no support for YP.)
208 * Tom Quinn has contributed a port of the C library to SGI machines running
209 Irix 4 (mips-sgi-irix4).
211 * The new `lockf' function is a simplified interface to the locking
212 facilities of `fcntl', included for compatibility.
214 * New time functions `timegm', `timelocal', and `dysize' for compatibility.
216 * New header file <sys/timeb.h> and new function `ftime' for compatibility.
218 * New header files <poll.h> and <sys/poll.h> and new function `poll' for
221 * The error message printed by `assert' for a failed assertion now includes
222 the name of the program (if using GNU ld) and the name of the calling
223 function (with versions of GCC that support this).
225 * The `psignal' function is now declared in <signal.h>, not <stdio.h>.
227 * The library now includes the <sys/mman.h> header file and memory
228 management functions `mmap', `munmap', `mprotect', `msync', and
229 `madvise', on systems that support those facilities.
231 * The interface for `mcheck' has changed slightly: the function called to
232 abort the program when an allocation inconsistency is detected now takes
233 an argument that indicates the type of failure. The new function
234 `mprobe' lets you request a consistency check for a particular block at
235 any time (checks are normally done only when you call `free' or `realloc'
238 * It is now possible to easily cross-compile the C library, building on one
239 system a library to run on another machine and/or operating system. All
240 you need to do is set the variable `HOST_CC' in `configparms' to the
241 native compiler for programs to run on the machine you are building on (a
242 few generator programs are used on Unix systems); set `CC' to the
245 * The new function `fexecve' (only implemented on the GNU system) executes
246 a program file given a file descriptor already open on the file.
250 * Brendan Kehoe has contributed most of a port to the DEC Alpha
251 running OSF/1 (alpha-dec-osf1). He says it is 75% complete.
253 * You can set the variable `libprefix' in `configparms' to specify a prefix
254 to be prepended to installed library files; this makes it easy to install
255 the GNU C library to be linked as `-lgnuc' or whatever.
257 * The new `stpncpy' is a cross between `stpcpy' and `strncpy': It
258 copies a limited number of characters from a string, and returns the
259 address of the last character written.
261 * You no longer need to check for whether the installed `stddef.h' is
262 compatible with the GNU C library. configure now checks for you.
264 * You can now define a per-stream `fileno' function to convert the
265 stream's cookie into an integral file descriptor.
267 * ``malloc (0)'' no longer returns a null pointer. Instead, it
268 allocates zero bytes of storage, and returns a unique pointer which
269 you can pass to `realloc' or `free'. The behavior is undefined if
270 you dereference this pointer.
272 * The C library now runs on Sony NEWS m68k machines running either
273 NewsOS 3 or NewsOS 4.
275 * The new `syscall' function is a system-dependent primitive function
276 for invoking system calls. It has the canonical behavior on Unix
277 systems, including unreliable return values for some calls (such as
278 `pipe', `fork' and `getppid').
280 * The error code `EWOULDBLOCK' is now obsolete; it is always defined
281 to `EAGAIN', which is the preferred name. On systems whose kernels
282 use two distinct codes, the C library now translates EWOULDBLOCK to
283 EAGAIN in every system call function.
287 * The GNU C Library Reference Manual is now distributed with the library.
288 `make dvi' will produce a DVI file of the printed manual.
289 `make info' will produce Info files that you can read on line using C-h i
290 in Emacs or the `info' program.
291 Please send comments on the manual to bug-glibc-manual@prep.ai.mit.edu.
293 * The library now supports SVR4 on i386s (i386-unknown-sysv4).
295 * Brendan Kehoe has contributed a port to Sun SPARCs running Solaris 2.
297 * Jason Merrill has contributed a port to the Sequent Symmetry running
298 Dynix version 3 (i386-sequent-dynix).
300 * The library has been ported to i386s running SCO 3.2.4 (also known as SCO
301 ODT 2.0; i386-unknown-sco3.2.4) or SCO 3.2 (i386-unknown-sco3.2).
303 * New function `memory_warnings' lets you arrange to get warnings when
304 malloc is running out of memory to allocate, like Emacs gives you.
306 * The C library now contains the relocating allocator used in Emacs 19 for
307 its editing buffers. This allocator (ralloc) minimizes allocation
308 overhead and fragmentation by moving allocated regions around whenever it
309 needs to. You always refer to a ralloc'd region with a "handle" (a
310 pointer to a pointer--an object of type `void **').
312 * There is a new `printf' format: `%m' gives you the string corresponding
313 to the error code in `errno'.
315 * In `scanf' formats, you can now use `%as' or `%a[' to do the normal `%s'
316 or `%[' conversion, but instead of filling in a fixed-sized buffer you
317 pass, the `a' modifier says to fill in a `char **' you pass with a
320 * The `fnmatch' function supports the new flag bits `FNM_LEADING_DIR' and
321 `FNM_CASEFOLD'. `FNM_LEADING_DIR' lets a pattern like `foo*' match a
322 name like `foo/bar'. `FNM_CASEFOLD' says to ignore case in matching.
324 * `mkstemp' is a traditional Unix function to atomically create and open a
325 uniquely-named temporary file.
329 * The standard location for the file that says what the local timezone is
330 has changed again. It is now `/usr/local/etc/localtime' (or more
331 precisely, `${prefix}/etc/localtime') rather than `/etc/localtime'.
333 * The distribution no longer contains any files with names longer than 14
336 * `struct ttyent' has two new flag bits: TTY_TRUSTED and TTY_CONSOLE.
337 These are set by the new `trusted' and `console' keywords in `/etc/ttys'.
339 * New functions `ttyslot' and `syslog' from 4.4 BSD.
343 * The configuration process has changed quite a bit. The `configure'
344 script is now used just like the configuration scripts for other GNU
345 packages. The `sysdeps' directory hierarchy is much rearranged.
346 The file `INSTALL' explains the new scheme in detail.
348 * The header files no longer need to be processed into ANSI C and
349 traditional C versions. There is just one set of files to install, and
350 it will work with ANSI or old C compilers (including `gcc -traditional').
352 * Brendan Kehoe and Ian Lance Taylor have ported the library to the
353 MIPS DECStation running Ultrix 4.
355 * The Sun 4 startup code (crt0) can now properly load SunOS 4 shared libraries.
356 Tom Quinn contributed the initial code. The GNU C library can NOT yet be
357 made itself into a shared library.
359 * Yet further improved support for the i386, running 4.3 BSD-like systems
360 (such as Mach 3 with the Unix single-server), or System V.
362 * New function `strncasecmp' to do case-insensitive string comparison
365 * New function `strsep' is a reentrant alternative to `strtok'.
367 * New functions `scandir' and `alphasort' for searching directories.
369 * New function `setenv' is a better interface to `putenv'.
371 * Ian Lance Taylor has contributed an implementation of the SVID `ftw'
372 function for traversing a directory tree.
374 * The GNU obstack package is now also part of the C library.
375 The new function `open_obstack_stream' creates a stdio stream that
376 writes onto an obstack; `obstack_printf' and `obstack_vprintf' do
377 formatted output directly to an obstack.
379 * Miscellaneous new functions: reboot, nice, sigaltstack (4.4 BSD only),
380 cfmakeraw, getusershell, getpass, swab, getttyent, seteuid, setegid.
382 * `FNM_FILE_NAME' is another name for `FNM_PATHNAME', used with `fnmatch'.
384 * The new functions `strfry' and `memfrob' do mysterious and wonderful
385 things to your strings.
387 * There are some new test programs: test-fseek, testmb, and testrand.
389 * Some work has been done to begin porting the library to 4.4 BSD and Linux.
390 These ports are not finished, but are a good starting place for really
391 supporting those systems.
393 * `/etc/localtime' is now the standard location for the file that says what
394 the local timezone is, rather than `/usr/local/lib/zoneinfo/localtime'.
395 This follows the general principle that `/etc' is the place for all local
398 * The C library header files now use `extern "C"' when used by the C++
399 compiler, so the C library should now work with C++ code.
401 * The header file <bstring.h> is gone. <string.h> now declares bcopy,
402 bcmp, bzero, and ffs.
404 * Mike Haertel (of GNU e?grep and malloc fame) has written a new sorting
405 function which uses the `merge sort' algorithm, and is said to be
406 significantly faster than the old GNU `qsort' function. Merge sort is
407 now the standard `qsort' function. The new algorithm can require a lot
408 of temporary storage; so, the old sorting function is called when the
409 required storage is not available.
411 * The C library now includes Michael Glad's Ultra Fast Crypt, which
412 provides the Unix `crypt' function, plus some other entry points.
413 Because of the United States export restriction on DES implementations,
414 we are distributing this code separately from the rest of the C library.
415 There is an extra distribution tar file just for crypt; it is called
416 `glibc-VERSION-crypt.tar.Z', e.g. `glibc-1.04-crypt.tar.Z'. You can just
417 unpack the crypt distribution along with the rest of the C library and
418 build; you can also build the library without getting crypt. Users
419 outside the USA can get the crypt distribution via anonymous FTP from
420 ftp.uni-c.dk [129.142.6.74], or another archive site outside the U.S.
422 * The code and header files taken from 4.4 BSD have been updated with the
423 latest files released from Berkeley.
425 ----------------------------------------------------------------------
426 Copyright information:
428 Copyright (C) 1992, 93, 94, 95, 96 Free Software Foundation, Inc.
430 Permission is granted to anyone to make or distribute verbatim copies
431 of this document as received, in any medium, provided that the
432 copyright notice and this permission notice are preserved,
433 thus giving the recipient permission to redistribute in turn.
435 Permission is granted to distribute modified versions
436 of this document, or of portions of it,
437 under the above conditions, provided also that they
438 carry prominent notices stating who last changed them.
441 version-control: never