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+'\"
+'\" Copyright (c) 1995-1996 Sun Microsystems, Inc.
+'\"
+'\" See the file "license.terms" for information on usage and redistribution
+'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES.
+'\"
+'\" SCCS: @(#) load.n 1.9 97/08/22 18:51:18
+'\"
+.so man.macros
+.TH load n 7.5 Tcl "Tcl Built-In Commands"
+.BS
+'\" Note: do not modify the .SH NAME line immediately below!
+.SH NAME
+load \- Load machine code and initialize new commands.
+.SH SYNOPSIS
+\fBload \fIfileName\fR
+.br
+\fBload \fIfileName packageName\fR
+.br
+\fBload \fIfileName packageName interp\fR
+.BE
+
+.SH DESCRIPTION
+.PP
+This command loads binary code from a file into the
+application's address space and calls an initialization procedure
+in the package to incorporate it into an interpreter. \fIfileName\fR
+is the name of the file containing the code; its exact form varies
+from system to system but on most systems it is a shared library,
+such as a \fB.so\fR file under Solaris or a DLL under Windows.
+\fIpackageName\fR is the name of the package, and is used to
+compute the name of an initialization procedure.
+\fIinterp\fR is the path name of the interpreter into which to load
+the package (see the \fBinterp\fR manual entry for details);
+if \fIinterp\fR is omitted, it defaults to the
+interpreter in which the \fBload\fR command was invoked.
+.PP
+Once the file has been loaded into the application's address space,
+one of two initialization procedures will be invoked in the new code.
+Typically the initialization procedure will add new commands to a
+Tcl interpreter.
+The name of the initialization procedure is determined by
+\fIpackageName\fR and whether or not the target interpreter
+is a safe one. For normal interpreters the name of the initialization
+procedure will have the form \fIpkg\fB_Init\fR, where \fIpkg\fR
+is the same as \fIpackageName\fR except that the first letter is
+converted to upper case and all other letters
+are converted to lower case. For example, if \fIpackageName\fR is
+\fBfoo\fR or \fBFOo\fR, the initialization procedure's name will
+be \fBFoo_Init\fR.
+.PP
+If the target interpreter is a safe interpreter, then the name
+of the initialization procedure will be \fIpkg\fB_SafeInit\fR
+instead of \fIpkg\fB_Init\fR.
+The \fIpkg\fB_SafeInit\fR function should be written carefully, so that it
+initializes the safe interpreter only with partial functionality provided
+by the package that is safe for use by untrusted code. For more information
+on Safe\-Tcl, see the \fBsafe\fR manual entry.
+.PP
+The initialization procedure must match the following prototype:
+.CS
+typedef int Tcl_PackageInitProc(Tcl_Interp *\fIinterp\fR);
+.CE
+The \fIinterp\fR argument identifies the interpreter in which the
+package is to be loaded. The initialization procedure must return
+\fBTCL_OK\fR or \fBTCL_ERROR\fR to indicate whether or not it completed
+successfully; in the event of an error it should set \fIinterp->result\fR
+to point to an error message. The result of the \fBload\fR command
+will be the result returned by the initialization procedure.
+.PP
+The actual loading of a file will only be done once for each \fIfileName\fR
+in an application. If a given \fIfileName\fR is loaded into multiple
+interpreters, then the first \fBload\fR will load the code and
+call the initialization procedure; subsequent \fBload\fRs will
+call the initialization procedure without loading the code again.
+It is not possible to unload or reload a package.
+.PP
+The \fBload\fR command also supports packages that are statically
+linked with the application, if those packages have been registered
+by calling the \fBTcl_StaticPackage\fR procedure.
+If \fIfileName\fR is an empty string, then \fIpackageName\fR must
+be specified.
+.PP
+If \fIpackageName\fR is omitted or specified as an empty string,
+Tcl tries to guess the name of the package.
+This may be done differently on different platforms.
+The default guess, which is used on most UNIX platforms, is to
+take the last element of \fIfileName\fR, strip off the first
+three characters if they are \fBlib\fR, and use any following
+.VS
+alphabetic and underline characters as the module name.
+.VE
+For example, the command \fBload libxyz4.2.so\fR uses the module
+name \fBxyz\fR and the command \fBload bin/last.so {}\fR uses the
+module name \fBlast\fR.
+.VS "" br
+.PP
+If \fIfileName\fR is an empty string, then \fIpackageName\fR must
+be specified.
+The \fBload\fR command first searches for a statically loaded package
+(one that has been registered by calling the \fBTcl_StaticPackage\fR
+procedure) by that name; if one is found, it is used.
+Otherwise, the \fBload\fR command searches for a dynamically loaded
+package by that name, and uses it if it is found. If several
+different files have been \fBload\fRed with different versions of
+the package, Tcl picks the file that was loaded first.
+.VE
+
+.SH BUGS
+.PP
+If the same file is \fBload\fRed by different \fIfileName\fRs, it will
+be loaded into the process's address space multiple times. The
+behavior of this varies from system to system (some systems may
+detect the redundant loads, others may not).
+
+.SH "SEE ALSO"
+\fBinfo sharedlibextension\fR, Tcl_StaticPackage, safe(n)
+
+.SH KEYWORDS
+binary code, loading, safe interpreter, shared library