| 1 | '\" |
| 2 | '\" Copyright (c) 1995-1996 Sun Microsystems, Inc. |
| 3 | '\" |
| 4 | '\" See the file "license.terms" for information on usage and redistribution |
| 5 | '\" of this file, and for a DISCLAIMER OF ALL WARRANTIES. |
| 6 | '\" |
| 7 | '\" RCS: @(#) $Id: load.n,v 1.7.2.1 2004/10/27 12:52:40 dkf Exp $ |
| 8 | '\" |
| 9 | '\" The definitions below are for supplemental macros used in Tcl/Tk |
| 10 | '\" manual entries. |
| 11 | '\" |
| 12 | '\" .AP type name in/out ?indent? |
| 13 | '\" Start paragraph describing an argument to a library procedure. |
| 14 | '\" type is type of argument (int, etc.), in/out is either "in", "out", |
| 15 | '\" or "in/out" to describe whether procedure reads or modifies arg, |
| 16 | '\" and indent is equivalent to second arg of .IP (shouldn't ever be |
| 17 | '\" needed; use .AS below instead) |
| 18 | '\" |
| 19 | '\" .AS ?type? ?name? |
| 20 | '\" Give maximum sizes of arguments for setting tab stops. Type and |
| 21 | '\" name are examples of largest possible arguments that will be passed |
| 22 | '\" to .AP later. If args are omitted, default tab stops are used. |
| 23 | '\" |
| 24 | '\" .BS |
| 25 | '\" Start box enclosure. From here until next .BE, everything will be |
| 26 | '\" enclosed in one large box. |
| 27 | '\" |
| 28 | '\" .BE |
| 29 | '\" End of box enclosure. |
| 30 | '\" |
| 31 | '\" .CS |
| 32 | '\" Begin code excerpt. |
| 33 | '\" |
| 34 | '\" .CE |
| 35 | '\" End code excerpt. |
| 36 | '\" |
| 37 | '\" .VS ?version? ?br? |
| 38 | '\" Begin vertical sidebar, for use in marking newly-changed parts |
| 39 | '\" of man pages. The first argument is ignored and used for recording |
| 40 | '\" the version when the .VS was added, so that the sidebars can be |
| 41 | '\" found and removed when they reach a certain age. If another argument |
| 42 | '\" is present, then a line break is forced before starting the sidebar. |
| 43 | '\" |
| 44 | '\" .VE |
| 45 | '\" End of vertical sidebar. |
| 46 | '\" |
| 47 | '\" .DS |
| 48 | '\" Begin an indented unfilled display. |
| 49 | '\" |
| 50 | '\" .DE |
| 51 | '\" End of indented unfilled display. |
| 52 | '\" |
| 53 | '\" .SO |
| 54 | '\" Start of list of standard options for a Tk widget. The |
| 55 | '\" options follow on successive lines, in four columns separated |
| 56 | '\" by tabs. |
| 57 | '\" |
| 58 | '\" .SE |
| 59 | '\" End of list of standard options for a Tk widget. |
| 60 | '\" |
| 61 | '\" .OP cmdName dbName dbClass |
| 62 | '\" Start of description of a specific option. cmdName gives the |
| 63 | '\" option's name as specified in the class command, dbName gives |
| 64 | '\" the option's name in the option database, and dbClass gives |
| 65 | '\" the option's class in the option database. |
| 66 | '\" |
| 67 | '\" .UL arg1 arg2 |
| 68 | '\" Print arg1 underlined, then print arg2 normally. |
| 69 | '\" |
| 70 | '\" RCS: @(#) $Id: man.macros,v 1.4 2000/08/25 06:18:32 ericm Exp $ |
| 71 | '\" |
| 72 | '\" # Set up traps and other miscellaneous stuff for Tcl/Tk man pages. |
| 73 | .if t .wh -1.3i ^B |
| 74 | .nr ^l \n(.l |
| 75 | .ad b |
| 76 | '\" # Start an argument description |
| 77 | .de AP |
| 78 | .ie !"\\$4"" .TP \\$4 |
| 79 | .el \{\ |
| 80 | . ie !"\\$2"" .TP \\n()Cu |
| 81 | . el .TP 15 |
| 82 | .\} |
| 83 | .ta \\n()Au \\n()Bu |
| 84 | .ie !"\\$3"" \{\ |
| 85 | \&\\$1 \\fI\\$2\\fP (\\$3) |
| 86 | .\".b |
| 87 | .\} |
| 88 | .el \{\ |
| 89 | .br |
| 90 | .ie !"\\$2"" \{\ |
| 91 | \&\\$1 \\fI\\$2\\fP |
| 92 | .\} |
| 93 | .el \{\ |
| 94 | \&\\fI\\$1\\fP |
| 95 | .\} |
| 96 | .\} |
| 97 | .. |
| 98 | '\" # define tabbing values for .AP |
| 99 | .de AS |
| 100 | .nr )A 10n |
| 101 | .if !"\\$1"" .nr )A \\w'\\$1'u+3n |
| 102 | .nr )B \\n()Au+15n |
| 103 | .\" |
| 104 | .if !"\\$2"" .nr )B \\w'\\$2'u+\\n()Au+3n |
| 105 | .nr )C \\n()Bu+\\w'(in/out)'u+2n |
| 106 | .. |
| 107 | .AS Tcl_Interp Tcl_CreateInterp in/out |
| 108 | '\" # BS - start boxed text |
| 109 | '\" # ^y = starting y location |
| 110 | '\" # ^b = 1 |
| 111 | .de BS |
| 112 | .br |
| 113 | .mk ^y |
| 114 | .nr ^b 1u |
| 115 | .if n .nf |
| 116 | .if n .ti 0 |
| 117 | .if n \l'\\n(.lu\(ul' |
| 118 | .if n .fi |
| 119 | .. |
| 120 | '\" # BE - end boxed text (draw box now) |
| 121 | .de BE |
| 122 | .nf |
| 123 | .ti 0 |
| 124 | .mk ^t |
| 125 | .ie n \l'\\n(^lu\(ul' |
| 126 | .el \{\ |
| 127 | .\" Draw four-sided box normally, but don't draw top of |
| 128 | .\" box if the box started on an earlier page. |
| 129 | .ie !\\n(^b-1 \{\ |
| 130 | \h'-1.5n'\L'|\\n(^yu-1v'\l'\\n(^lu+3n\(ul'\L'\\n(^tu+1v-\\n(^yu'\l'|0u-1.5n\(ul' |
| 131 | .\} |
| 132 | .el \}\ |
| 133 | \h'-1.5n'\L'|\\n(^yu-1v'\h'\\n(^lu+3n'\L'\\n(^tu+1v-\\n(^yu'\l'|0u-1.5n\(ul' |
| 134 | .\} |
| 135 | .\} |
| 136 | .fi |
| 137 | .br |
| 138 | .nr ^b 0 |
| 139 | .. |
| 140 | '\" # VS - start vertical sidebar |
| 141 | '\" # ^Y = starting y location |
| 142 | '\" # ^v = 1 (for troff; for nroff this doesn't matter) |
| 143 | .de VS |
| 144 | .if !"\\$2"" .br |
| 145 | .mk ^Y |
| 146 | .ie n 'mc \s12\(br\s0 |
| 147 | .el .nr ^v 1u |
| 148 | .. |
| 149 | '\" # VE - end of vertical sidebar |
| 150 | .de VE |
| 151 | .ie n 'mc |
| 152 | .el \{\ |
| 153 | .ev 2 |
| 154 | .nf |
| 155 | .ti 0 |
| 156 | .mk ^t |
| 157 | \h'|\\n(^lu+3n'\L'|\\n(^Yu-1v\(bv'\v'\\n(^tu+1v-\\n(^Yu'\h'-|\\n(^lu+3n' |
| 158 | .sp -1 |
| 159 | .fi |
| 160 | .ev |
| 161 | .\} |
| 162 | .nr ^v 0 |
| 163 | .. |
| 164 | '\" # Special macro to handle page bottom: finish off current |
| 165 | '\" # box/sidebar if in box/sidebar mode, then invoked standard |
| 166 | '\" # page bottom macro. |
| 167 | .de ^B |
| 168 | .ev 2 |
| 169 | 'ti 0 |
| 170 | 'nf |
| 171 | .mk ^t |
| 172 | .if \\n(^b \{\ |
| 173 | .\" Draw three-sided box if this is the box's first page, |
| 174 | .\" draw two sides but no top otherwise. |
| 175 | .ie !\\n(^b-1 \h'-1.5n'\L'|\\n(^yu-1v'\l'\\n(^lu+3n\(ul'\L'\\n(^tu+1v-\\n(^yu'\h'|0u'\c |
| 176 | .el \h'-1.5n'\L'|\\n(^yu-1v'\h'\\n(^lu+3n'\L'\\n(^tu+1v-\\n(^yu'\h'|0u'\c |
| 177 | .\} |
| 178 | .if \\n(^v \{\ |
| 179 | .nr ^x \\n(^tu+1v-\\n(^Yu |
| 180 | \kx\h'-\\nxu'\h'|\\n(^lu+3n'\ky\L'-\\n(^xu'\v'\\n(^xu'\h'|0u'\c |
| 181 | .\} |
| 182 | .bp |
| 183 | 'fi |
| 184 | .ev |
| 185 | .if \\n(^b \{\ |
| 186 | .mk ^y |
| 187 | .nr ^b 2 |
| 188 | .\} |
| 189 | .if \\n(^v \{\ |
| 190 | .mk ^Y |
| 191 | .\} |
| 192 | .. |
| 193 | '\" # DS - begin display |
| 194 | .de DS |
| 195 | .RS |
| 196 | .nf |
| 197 | .sp |
| 198 | .. |
| 199 | '\" # DE - end display |
| 200 | .de DE |
| 201 | .fi |
| 202 | .RE |
| 203 | .sp |
| 204 | .. |
| 205 | '\" # SO - start of list of standard options |
| 206 | .de SO |
| 207 | .SH "STANDARD OPTIONS" |
| 208 | .LP |
| 209 | .nf |
| 210 | .ta 5.5c 11c |
| 211 | .ft B |
| 212 | .. |
| 213 | '\" # SE - end of list of standard options |
| 214 | .de SE |
| 215 | .fi |
| 216 | .ft R |
| 217 | .LP |
| 218 | See the \\fBoptions\\fR manual entry for details on the standard options. |
| 219 | .. |
| 220 | '\" # OP - start of full description for a single option |
| 221 | .de OP |
| 222 | .LP |
| 223 | .nf |
| 224 | .ta 4c |
| 225 | Command-Line Name: \\fB\\$1\\fR |
| 226 | Database Name: \\fB\\$2\\fR |
| 227 | Database Class: \\fB\\$3\\fR |
| 228 | .fi |
| 229 | .IP |
| 230 | .. |
| 231 | '\" # CS - begin code excerpt |
| 232 | .de CS |
| 233 | .RS |
| 234 | .nf |
| 235 | .ta .25i .5i .75i 1i |
| 236 | .. |
| 237 | '\" # CE - end code excerpt |
| 238 | .de CE |
| 239 | .fi |
| 240 | .RE |
| 241 | .. |
| 242 | .de UL |
| 243 | \\$1\l'|0\(ul'\\$2 |
| 244 | .. |
| 245 | .TH load n 7.5 Tcl "Tcl Built-In Commands" |
| 246 | .BS |
| 247 | '\" Note: do not modify the .SH NAME line immediately below! |
| 248 | .SH NAME |
| 249 | load \- Load machine code and initialize new commands. |
| 250 | .SH SYNOPSIS |
| 251 | \fBload \fIfileName\fR |
| 252 | .br |
| 253 | \fBload \fIfileName packageName\fR |
| 254 | .br |
| 255 | \fBload \fIfileName packageName interp\fR |
| 256 | .BE |
| 257 | |
| 258 | .SH DESCRIPTION |
| 259 | .PP |
| 260 | This command loads binary code from a file into the |
| 261 | application's address space and calls an initialization procedure |
| 262 | in the package to incorporate it into an interpreter. \fIfileName\fR |
| 263 | is the name of the file containing the code; its exact form varies |
| 264 | from system to system but on most systems it is a shared library, |
| 265 | such as a \fB.so\fR file under Solaris or a DLL under Windows. |
| 266 | \fIpackageName\fR is the name of the package, and is used to |
| 267 | compute the name of an initialization procedure. |
| 268 | \fIinterp\fR is the path name of the interpreter into which to load |
| 269 | the package (see the \fBinterp\fR manual entry for details); |
| 270 | if \fIinterp\fR is omitted, it defaults to the |
| 271 | interpreter in which the \fBload\fR command was invoked. |
| 272 | .PP |
| 273 | Once the file has been loaded into the application's address space, |
| 274 | one of two initialization procedures will be invoked in the new code. |
| 275 | Typically the initialization procedure will add new commands to a |
| 276 | Tcl interpreter. |
| 277 | The name of the initialization procedure is determined by |
| 278 | \fIpackageName\fR and whether or not the target interpreter |
| 279 | is a safe one. For normal interpreters the name of the initialization |
| 280 | procedure will have the form \fIpkg\fB_Init\fR, where \fIpkg\fR |
| 281 | is the same as \fIpackageName\fR except that the first letter is |
| 282 | converted to upper case and all other letters |
| 283 | are converted to lower case. For example, if \fIpackageName\fR is |
| 284 | \fBfoo\fR or \fBFOo\fR, the initialization procedure's name will |
| 285 | be \fBFoo_Init\fR. |
| 286 | .PP |
| 287 | If the target interpreter is a safe interpreter, then the name |
| 288 | of the initialization procedure will be \fIpkg\fB_SafeInit\fR |
| 289 | instead of \fIpkg\fB_Init\fR. |
| 290 | The \fIpkg\fB_SafeInit\fR function should be written carefully, so that it |
| 291 | initializes the safe interpreter only with partial functionality provided |
| 292 | by the package that is safe for use by untrusted code. For more information |
| 293 | on Safe\-Tcl, see the \fBsafe\fR manual entry. |
| 294 | .PP |
| 295 | The initialization procedure must match the following prototype: |
| 296 | .CS |
| 297 | typedef int Tcl_PackageInitProc(Tcl_Interp *\fIinterp\fR); |
| 298 | .CE |
| 299 | The \fIinterp\fR argument identifies the interpreter in which the |
| 300 | package is to be loaded. The initialization procedure must return |
| 301 | \fBTCL_OK\fR or \fBTCL_ERROR\fR to indicate whether or not it completed |
| 302 | successfully; in the event of an error it should set the interpreter's result |
| 303 | to point to an error message. The result of the \fBload\fR command |
| 304 | will be the result returned by the initialization procedure. |
| 305 | .PP |
| 306 | The actual loading of a file will only be done once for each \fIfileName\fR |
| 307 | in an application. If a given \fIfileName\fR is loaded into multiple |
| 308 | interpreters, then the first \fBload\fR will load the code and |
| 309 | call the initialization procedure; subsequent \fBload\fRs will |
| 310 | call the initialization procedure without loading the code again. |
| 311 | It is not possible to unload or reload a package. |
| 312 | .PP |
| 313 | The \fBload\fR command also supports packages that are statically |
| 314 | linked with the application, if those packages have been registered |
| 315 | by calling the \fBTcl_StaticPackage\fR procedure. |
| 316 | If \fIfileName\fR is an empty string, then \fIpackageName\fR must |
| 317 | be specified. |
| 318 | .PP |
| 319 | If \fIpackageName\fR is omitted or specified as an empty string, |
| 320 | Tcl tries to guess the name of the package. |
| 321 | This may be done differently on different platforms. |
| 322 | The default guess, which is used on most UNIX platforms, is to |
| 323 | take the last element of \fIfileName\fR, strip off the first |
| 324 | three characters if they are \fBlib\fR, and use any following |
| 325 | .VS |
| 326 | alphabetic and underline characters as the module name. |
| 327 | .VE |
| 328 | For example, the command \fBload libxyz4.2.so\fR uses the module |
| 329 | name \fBxyz\fR and the command \fBload bin/last.so {}\fR uses the |
| 330 | module name \fBlast\fR. |
| 331 | .VS "" br |
| 332 | .PP |
| 333 | If \fIfileName\fR is an empty string, then \fIpackageName\fR must |
| 334 | be specified. |
| 335 | The \fBload\fR command first searches for a statically loaded package |
| 336 | (one that has been registered by calling the \fBTcl_StaticPackage\fR |
| 337 | procedure) by that name; if one is found, it is used. |
| 338 | Otherwise, the \fBload\fR command searches for a dynamically loaded |
| 339 | package by that name, and uses it if it is found. If several |
| 340 | different files have been \fBload\fRed with different versions of |
| 341 | the package, Tcl picks the file that was loaded first. |
| 342 | .VE |
| 343 | .SH "PORTABILITY ISSUES" |
| 344 | .TP |
| 345 | \fBWindows\fR\0\0\0\0\0 |
| 346 | . |
| 347 | When a load fails with "library not found" error, it is also possible |
| 348 | that a dependent library was not found. To see the dependent libraries, |
| 349 | type ``dumpbin -imports <dllname>'' in a DOS console to see what the |
| 350 | library must import. |
| 351 | When loading a DLL in the current directory, Windows will ignore ``./'' as |
| 352 | a path specifier and use a search heuristic to find the DLL instead. |
| 353 | To avoid this, load the DLL with: |
| 354 | .CS |
| 355 | \fBload\fR [file join [pwd] mylib.DLL] |
| 356 | .CE |
| 357 | .SH BUGS |
| 358 | .PP |
| 359 | If the same file is \fBload\fRed by different \fIfileName\fRs, it will |
| 360 | be loaded into the process's address space multiple times. The |
| 361 | behavior of this varies from system to system (some systems may |
| 362 | detect the redundant loads, others may not). |
| 363 | .SH EXAMPLE |
| 364 | The following is a minimal extension: |
| 365 | .PP |
| 366 | .CS |
| 367 | #include <tcl.h> |
| 368 | #include <stdio.h> |
| 369 | static int fooCmd(ClientData clientData, |
| 370 | Tcl_Interp *interp, int objc, char * CONST objv[]) { |
| 371 | printf("called with %d arguments\\n", objc); |
| 372 | return TCL_OK; |
| 373 | } |
| 374 | int Foo_Init(Tcl_Interp *interp) { |
| 375 | if (Tcl_InitStubs(interp, "8.1", 0) == NULL) { |
| 376 | return TCL_ERROR; |
| 377 | } |
| 378 | printf("creating foo command"); |
| 379 | Tcl_CreateObjCommand(interp, "foo", fooCmd, NULL, NULL); |
| 380 | return TCL_OK; |
| 381 | } |
| 382 | .CE |
| 383 | .PP |
| 384 | When built into a shared/dynamic library with a suitable name |
| 385 | (e.g. \fBfoo.dll\fR on Windows, \fBlibfoo.so\fR on Solaris and Linux) |
| 386 | it can then be loaded into Tcl with the following: |
| 387 | .PP |
| 388 | .CS |
| 389 | # Load the extension |
| 390 | switch $tcl_platform(platform) { |
| 391 | windows { |
| 392 | \fBload\fR ./foo.dll |
| 393 | } |
| 394 | unix { |
| 395 | \fBload\fR ./libfoo[info sharedlibextension] |
| 396 | } |
| 397 | } |
| 398 | |
| 399 | # Now execute the command defined by the extension |
| 400 | foo |
| 401 | .CE |
| 402 | |
| 403 | .SH "SEE ALSO" |
| 404 | info sharedlibextension, Tcl_StaticPackage(3), safe(n) |
| 405 | |
| 406 | .SH KEYWORDS |
| 407 | binary code, loading, safe interpreter, shared library |