changes

tcl是工具命令语言

Tcl_DStringFree, Tcl_DStringResult, etc.

163. 3/1/93 Modified glob command to only return the names of files that
exist, and to only return names ending in "/" if the file is a directory.
*** POTENTIAL INCOMPATIBILITY ***

164. 3/19/93 Modified not to use system calls like "read" directly,
but instead to use special Tcl procedures that retry automatically
if interrupted by signals.

165. 4/3/93 Eliminated "noSep" argument to Tcl_AppendElement, plus
TCL_NO_SPACE flag for Tcl_SetVar and Tcl_SetVar2.
*** POTENTIAL INCOMPATIBILITY ***

166. 4/3/93 Eliminated "flags" and "termPtr" arguments to Tcl_Eval.
*** POTENTIAL INCOMPATIBILITY ***

167. 4/3/93 Changes to expressions:
    - The "expr" command now accepts multiple arguments, which are
      concatenated together with space separators.
    - Integers aren't automatically promoted to floating-point if they
      overflow the word size:  errors are generated instead.
    - Tcl can now handle "NaN" and other special values if the underlying
      library procedures handle them.
    - When printing floating-point numbers, Tcl ensures that there is a "."
      or "e" in the number, so it can't be treated as an integer accidentally.
      The procedure Tcl_PrintDouble is available to provide this function
      in other contexts.  Also, the variable "tcl_precision" can be used
      to set the precision for printing (must be a decimal number giving
      digits of precision).
    - Expressions now support transcendental and other functions, e.g. sin,
      acos, hypot, ceil, and round.  Can add new math functions with
      Tcl_CreateMathFunc().
    - Boolean expressions can now have any of the string values accepted
      by Tcl_GetBoolean, such as "yes" or "no".
*** POTENTIAL INCOMPATIBILITY ***

168. 4/5/93 Changed Tcl_UnsetVar and Tcl_UnsetVar2 to return TCL_OK
or TCL_ERROR instead of 0 or -1.
*** POTENTIAL INCOMPATIBILITY ***

169. 4/5/93 Eliminated Tcl_CmdBuf structure and associated procedures;
can use Tcl_DStrings instead.
*** POTENTIAL INCOMPATIBILITY ***

170. 4/8/93 Changed interface to Tcl_TildeSubst to use a dynamic
string for buffer space.  This makes the procedure re-entrant and
thread-safe, whereas it wasn't before.
*** POTENTIAL INCOMPATIBILITY ***

171. 4/14/93 Eliminated tclHash.h, and moved everything from it to
tcl.h
*** POTENTIAL INCOMPATIBILITY ***

172. 4/15/93 Eliminated Tcl_InitHistory, made "history" command always
be part of interpreter.
*** POTENTIAL INCOMPATIBILITY ***

173. 4/16/93 Modified "file" command so that "readable" option always
exists, even on machines that don't support symbolic links (always returns
same error as if the file wasn't a symbolic link).

174. 4/26/93 Fixed bugs in "regsub" where ^ patterns didn't get handled
right (pretended not to match when it really did, and looped infinitely
if -all was specified).

175. 4/29/93 Various improvements in the handling of variables:
    - Can create variables and array elements during a read trace.
    - Can delete variables during traces (note: unset traces will be
      invoked when this happens).
    - Can upvar to array elements.
    - Can retarget an upvar to another variable by re-issuing the
      upvar command with a different "other" variable.

176. 5/3/93 Added Tcl_GetCommandInfo, which returns info about a Tcl
command such as whether it exists and its ClientData.  Also added
Tcl_SetCommandInfo, which allows any of this information to be modified
and also allows a command's delete procedure to have a different
ClientData value than its command procedure.

177. 5/5/93 Added Tcl_RegExpMatch procedure.

178. 5/6/93 Fixed bug in "scan" where it didn't properly handle
%% conversion specifiers.  Also changed "scan" to use Tcl_PrintDouble
for printing real values.

179. 5/7/93 Added "-exact", "-glob", and "-regexp" options to "lsearch"
command to allow different kinds of pattern matching.

180. 5/7/93 Added many new switches to "lsort" to control the sorting
process: "-ascii", "-integer", "-real", "-command", "-increasing",
and "-decreasing".

181. 5/10/93 Changes to file I/O:
    - Modified "open" command to support a list of POSIX access flags
      like {WRONLY CREAT TRUNC} in addition to current fopen-style
      access modes.  Also added "permissions" argument to set permissions
      of newly-created files.
    - Fixed Scott Bolte's bug (can close stdin etc. in application and
      then re-open them with Tcl commands).
    - Exported access to Tcl's file table with new procedures Tcl_EnterFile
      and Tcl_GetOpenFile.

182. 5/15/93 Added new "pid" command, which can be used to retrieve
either the current process id or a list of the process ids in a
pipeline opened with "open |..."

183. 6/3/93 Changed to use GNU autoconfig for configuration instead of
the home-brew "config" script.  Also made many other configuration-related
changes, such as using <unistd.h> instead of explicitly declaring system
calls in tclUnix.h.

184. 6/4/93 Fixed bug where core-dumps could occur if a procedure
redefined itself (the memory for the procedure's body could get
reallocated in the middle of evaluating the body);  implemented
simple reference count mechanism.

185. 6/5/93 Changed tclIndex file format in two ways:  (a) it's now
eval-ed instead of parsed, which makes it 3-4x faster; (b) the entries
in auto_index are now commands to evaluate, which allows commands to
be loaded in different ways such as dynamic-loading of C code.  The
old tclIndex file format is still supported.

186. 6/7/93 Eliminated tclTest program, added new "tclsh" program
that is more like wish (allows script files to be invoked automatically
using "#!/usr/local/bin/tclsh", makes arguments available to script,
etc.).  Added support for Tcl_AppInit plus default version;  this
allows new Tcl applications to be created without modifying the
main program for tclsh.

187. 6/7/93 Fixed bug in TclWordEnd that kept backslash-newline from
working correctly in some cases during interactive input.

188. 6/9/93 Added Tcl_LinkVar and related procedures, which automatically
keep a Tcl variable in sync with a C variable.

189. 6/16/93 Increased maximum nesting depth from 100 to 1000.

190. 6/16/93 Modified "trace var" command so that error messages from
within traces are returned properly as the result of the variable
access, instead of the generic "access disallowed by trace command"
message.

191. 6/16/93 Added Tcl_CallWhenDeleted to provide callbacks when an
interpreter is deleted (same functionality as Tcl_WatchInterp, which
used to exist in versions before 6.0).

193. 6/16/93 Added "-code" argument to "return" command;  it's there
primarily for completeness, so that procedures implementing control
constructs can reflect exceptional conditions back to their callers.

194. 6/16/93 Split up Tcl.n to make separate manual entries for each
Tcl command.  Tcl.n now contains a summary of the language syntax.

195. 6/17/93 Added new "switch" command to replace "case": allows
alternate forms of pattern matching (exact, glob, regexp), replaces
pattern lists with single patterns (but you can use "-" bodies to
share one body among several patterns), eliminates "in" noise word.
"Case" command is now obsolete.

196. 6/17/93 Changed the "exec", "glob", "regexp", and "regsub" commands
to include a "--" switch.  All initial arguments starting with "-" are now
treated as switches unless a "--" switch is present to end the list.
*** POTENTIAL INCOMPATIBILITY ***

197. 6/17/93 Changed auto-exec so that the subprocess gets stdin, stdout,
and stderr from the parent.  This allows truly interactive sub-processes
(e.g. vi) to be auto-exec'ed from a tcl shell command line.

198. 6/18/93 Added patchlevel.h, for use in coordinating future patch
releases, and also added "info patchlevel" command to make the patch
level available to Tcl scripts.

199. 6/19/93 Modified "glob" command so that a leading "//" in a name
gets left as is (this is needed for systems like Apollos where "//" is
the super-root;  Tcl used to collapse the two slashes into a single
slash).

200. 7/7/93 Added Tcl_SetRecursionLimit procedure so that the maximum
allowable nesting depth can be controlled for an interpreter from C.

----------------- Released version 7.0 Beta 1, 7/9/93 ------------------

201. 7/12/93 Modified Tcl_GetInt and tclExpr.c so that full-precision
unsigned integers can be specified without overflow errors.

202. 7/12/93 Configuration changes:  eliminate leading blank line in
configure script;  provide separate targets in Makefile for installing
binary and non-binary information; check for size_t and a few other
potentially missing typedefs; don't put tclAppInit.o into libtcl.a;
better checks for matherr support.

203. 7/14/93 Changed tclExpr.c to check the termination pointer before
errno after strtod calls, to avoid problems with some versions of
strtod that set errno in unexpected ways.

204. 7/16/93 Changed "scan" command to be more ANSI-conformant:
eliminated %F, %D, etc., added code to ignore "l", "h", and "L"
modifiers but always convert %e, %f, and %g with implicit "l";
also added support for %u and %i.  Also changed "format" command
to eliminate %D, %U, %O, and add %i.
*** POTENTIAL INCOMPATIBILITY ***

205. 7/17/93 Changed "uplevel" and "upvar" so that they can be used
from global level to global level:  this used to generate an error.

206. 7/19/93 Renamed "setenv", "putenv", and "unsetenv" procedures
to avoid conflicts with system procedures with the same names.  If
you want Tcl's procedures to override the system procedures, do it
in the Makefile (instructions are in the Makefile).
*** POTENTIAL INCOMPATIBILITY ***

----------------- Released version 7.0 Beta 2, 7/21/93 ------------------

207. 7/21/93 Fixed bug in tclVar.c where freed memory was accidentally
used if a procedure returned an element of a local array.

208. 7/22/93 Fixed bug in "unknown" where it didn't properly handle
errors occurring in the "auto_load" procedure, leaving its state
inconsistent.

209. 7/23/93 Changed exec's ">2" redirection operator to "2>" for
consistency with sh.  This is incompatible with earlier beta releases
of 7.0 but not with pre-7.0 releases, which didn't support either
operator.

210. 7/28/93 Changed backslash-newline handling so that the resulting
space character *is* treated as a word separator unless the backslash
sequence is in quotes or braces.  This is incompatible with 7.0b1
and 7.0b2 but is more compatible with pre-7.0 versions that the b1
and b2 releases were.

211. 7/28/93 Eliminated Tcl_LinkedVarWritable, added TCL_LINK_READ_ONLY to
Tcl_LinkVar to accomplish same purpose.  This change is incompatible
with earlier beta releases, but not with releases before Tcl 7.0.

212. 7/29/93 Renamed regexp C functions so they won't clash with POSIX
regexp functions that use the same name.

213. 8/3/93 Added "-errorinfo" and "-errorcode" options to "return"
command: these allow for much better handling of the errorInfo
and errorCode variables in some cases.

214. 8/12/93 Changed "expr" so that % always returns a remainder with
the same sign as the divisor and absolute value smaller than the
divisor.

215. 8/14/93 Turned off auto-exec in "unknown" unless the command
was typed interactively.  This means you must use "exec" when
invoking subprocesses, unless it's a command that's typed interactively.
*** POTENTIAL INCOMPATIBILITY ***

216. 8/14/93 Added support for tcl_prompt1 and tcl_prompt2 variables
to tclMain.c:  makes prompts user-settable.

217. 8/14/93 Added asynchronous handlers (Tcl_AsyncCreate etc.) so
that signals can be taken cleanly by Tcl applications.

218. 8/16/93 Moved information about open files from the interpreter
structure to global variables so that a file can be opened in one
interpreter and read or written in another.

219. 8/16/93 Removed ENV_FLAGS from Makefile, so that there's no
official support for overriding setenv, unsetenv, and putenv.

220. 8/20/93 Various configuration improvements:  coerce chars
to unsigned chars before using macros like isspace;  source ~/.tclshrc
file during initialization if it exists and program is running
interactively;  allow there to be directories in auto_path that don't
exist or don't have tclIndex files (ignore them); added Tcl_Init
procedure and changed Tcl_AppInit to call it.

221. 8/21/93 Fixed bug in expr where "+", "-", and " " were all
getting treated as integers with value 0.

222. 8/26/93 Added "tcl_interactive" variable to tclsh.

223. 8/27/93 Added procedure Tcl_FilePermissions to return whether a
given file can be read or written or both.  Modified Tcl_EnterFile
to take a permissions mask rather than separate read and write arguments.

224. 8/28/93 Fixed performance bug in "glob" command (unnecessary call
to "access" for each file caused a 5-10x slow-down for big directories).

----------------- Released version 7.0 Beta 3, 8/28/93 ------------------

225. 9/9/93 Renamed regexp.h to tclRegexp.h to avoid conflicts with system
include file by same name.

226. 9/9/93 Added Tcl_DontCallWhenDeleted.

227. 9/16/93 Changed not to call exit C procedure directly;  instead
always invoke "exit" Tcl command so that application can redefine the
command to do additional cleanup.

228. 9/17/93 Changed auto-exec to handle names that contain slashes
(i.e. don't use PATH for them).

229. 9/23/93 Fixed bug in "read" and "gets" commands where they didn't
clear EOF conditions.

----------------- Released version 7.0, 9/29/93 ------------------

230. 10/7/93 "Scan" command wasn't properly aligning things in memory,
so segmentation faults could arise under some circumstances.

231. 10/7/93 Fixed bug in Tcl_ConvertElement where it forgot to
backslash leading curly brace when creating lists.