Added a first crack at documentation for TIP #357's Tcl_LoadFile et al.

2 files changed, 96 insertions, 7 deletions

diff --git a/doc/FileSystem.3 b/doc/FileSystem.3
index caab40f..bc52214 100644
--- a/doc/FileSystem.3
+++ b/doc/FileSystem.3
@@ -1,17 +1,17 @@
 '\"
 '\" Copyright (c) 2001 Vincent Darley
-'\" Copyright (c) 2008 Donal K. Fellows
+'\" Copyright (c) 2008-2010 Donal K. Fellows
 '\"
 '\" See the file "license.terms" for information on usage and redistribution
 '\" of this file, and for a DISCLAIMER OF ALL WARRANTIES.
 '\" 
-'\" RCS: @(#) $Id: FileSystem.3,v 1.70 2010/01/14 11:47:07 dkf Exp $
+'\" RCS: @(#) $Id: FileSystem.3,v 1.71 2010/04/04 15:03:07 dkf Exp $
 '\" 
 .so man.macros
 .TH Filesystem 3 8.4 Tcl "Tcl Library Procedures"
 .BS
 .SH NAME
-Tcl_FSRegister, Tcl_FSUnregister, Tcl_FSData, Tcl_FSMountsChanged, Tcl_FSGetFileSystemForPath, Tcl_FSGetPathType, Tcl_FSCopyFile, Tcl_FSCopyDirectory, Tcl_FSCreateDirectory, Tcl_FSDeleteFile, Tcl_FSRemoveDirectory, Tcl_FSRenameFile, Tcl_FSListVolumes, Tcl_FSEvalFile, Tcl_FSEvalFileEx, Tcl_FSLoadFile, Tcl_FSMatchInDirectory, Tcl_FSLink, Tcl_FSLstat, Tcl_FSUtime, Tcl_FSFileAttrsGet, Tcl_FSFileAttrsSet, Tcl_FSFileAttrStrings, Tcl_FSStat, Tcl_FSAccess, Tcl_FSOpenFileChannel, Tcl_FSGetCwd, Tcl_FSChdir, Tcl_FSPathSeparator, Tcl_FSJoinPath, Tcl_FSSplitPath, Tcl_FSEqualPaths, Tcl_FSGetNormalizedPath, Tcl_FSJoinToPath, Tcl_FSConvertToPathType, Tcl_FSGetInternalRep, Tcl_FSGetTranslatedPath, Tcl_FSGetTranslatedStringPath, Tcl_FSNewNativePath, Tcl_FSGetNativePath, Tcl_FSFileSystemInfo, Tcl_GetAccessTimeFromStat, Tcl_GetBlockSizeFromStat, Tcl_GetBlocksFromStat, Tcl_GetChangeTimeFromStat, Tcl_GetDeviceTypeFromStat, Tcl_GetFSDeviceFromStat, Tcl_GetFSInodeFromStat, Tcl_GetGroupIdFromStat, Tcl_GetLinkCountFromStat, Tcl_GetModeFromStat, Tcl_GetModificationTimeFromStat, Tcl_GetSizeFromStat, Tcl_GetUserIdFromStat, Tcl_AllocStatBuf \- procedures to interact with any filesystem
+Tcl_FSRegister, Tcl_FSUnregister, Tcl_FSData, Tcl_FSMountsChanged, Tcl_FSGetFileSystemForPath, Tcl_FSGetPathType, Tcl_FSCopyFile, Tcl_FSCopyDirectory, Tcl_FSCreateDirectory, Tcl_FSDeleteFile, Tcl_FSRemoveDirectory, Tcl_FSRenameFile, Tcl_FSListVolumes, Tcl_FSEvalFile, Tcl_FSEvalFileEx, Tcl_FSLoadFile, Tcl_FSUnloadFile, Tcl_FSMatchInDirectory, Tcl_FSLink, Tcl_FSLstat, Tcl_FSUtime, Tcl_FSFileAttrsGet, Tcl_FSFileAttrsSet, Tcl_FSFileAttrStrings, Tcl_FSStat, Tcl_FSAccess, Tcl_FSOpenFileChannel, Tcl_FSGetCwd, Tcl_FSChdir, Tcl_FSPathSeparator, Tcl_FSJoinPath, Tcl_FSSplitPath, Tcl_FSEqualPaths, Tcl_FSGetNormalizedPath, Tcl_FSJoinToPath, Tcl_FSConvertToPathType, Tcl_FSGetInternalRep, Tcl_FSGetTranslatedPath, Tcl_FSGetTranslatedStringPath, Tcl_FSNewNativePath, Tcl_FSGetNativePath, Tcl_FSFileSystemInfo, Tcl_GetAccessTimeFromStat, Tcl_GetBlockSizeFromStat, Tcl_GetBlocksFromStat, Tcl_GetChangeTimeFromStat, Tcl_GetDeviceTypeFromStat, Tcl_GetFSDeviceFromStat, Tcl_GetFSInodeFromStat, Tcl_GetGroupIdFromStat, Tcl_GetLinkCountFromStat, Tcl_GetModeFromStat, Tcl_GetModificationTimeFromStat, Tcl_GetSizeFromStat, Tcl_GetUserIdFromStat, Tcl_AllocStatBuf \- procedures to interact with any filesystem
 .SH SYNOPSIS
 .nf
 \fB#include <tcl.h>\fR
@@ -63,7 +63,12 @@ int
 .sp
 int
 \fBTcl_FSLoadFile\fR(\fIinterp, pathPtr, sym1, sym2, proc1Ptr, proc2Ptr,
-               handlePtr, unloadProcPtr\fR)
+               loadHandlePtr, unloadProcPtr\fR)
+.sp
+.VS 8.6
+int
+\fBTcl_FSUnloadFile\fR(\fIinterp, loadHandle\fR)
+.VE 8.6
 .sp
 int
 \fBTcl_FSMatchInDirectory\fR(\fIinterp, resultPtr, pathPtr, pattern, types\fR)
@@ -249,10 +254,12 @@ Filled with the safe-init function for this code.
 .AP ClientData *clientDataPtr out
 Filled with the clientData value to pass to this code's unload
 function when it is called.
-.AP Tcl_LoadHandle *handlePtr out
+.AP Tcl_LoadHandle *loadHandlePtr out
 Filled with an abstract token representing the loaded file.
 .AP Tcl_FSUnloadFileProc **unloadProcPtr out
 Filled with the function to use to unload this piece of code.
+.AP Tcl_LoadHandle loadHandle in
+Handle to the loaded library to be unloaded.
 .AP utimbuf *tval in
 The access and modification times in this structure are read and
 used to set those values for a given file.
@@ -439,9 +446,20 @@ belongs will be called. If that filesystem does not implement this
 function (most virtual filesystems will not, because of OS limitations
 in dynamically loading binary code), Tcl will attempt to copy the file
 to a temporary directory and load that temporary file.
+.VS 8.6
+\fBTcl_FSUnloadFile\fR reverses the operation, asking for the library
+indicated by the \fIloadHandle\fR to be removed from the process. Note that,
+unlike with the \fBunload\fR command, this does not give the library any
+opportunity to clean up.
+.VE 8.6
 .PP
-Returns a standard Tcl completion code. If an error occurs, an error
-message is left in the \fIinterp\fR's result.
+Both the above functions return a standard Tcl completion code. If an error
+occurs, an error message is left in the \fIinterp\fR's result.
+.PP
+.VS 8.6
+The token provided via the variable indicated by \fIloadHandlePtr\fR may be
+used with \fBTcl_FindSymbol\fR.
+.VE 8.6
 .PP
 \fBTcl_FSMatchInDirectory\fR is used by the globbing code to search a
 directory for all files which match a given pattern. The appropriate
diff --git a/doc/Load.3 b/doc/Load.3
new file mode 100644
index 0000000..a8e8910
--- /dev/null
+++ b/doc/Load.3
@@ -0,0 +1,71 @@
+'\"
+'\" Copyright (c) 2009-2010 Kevin B. Kenny
+'\" Copyright (c) 2010 Donal K. Fellows
+'\"
+'\" See the file "license.terms" for information on usage and redistribution
+'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES.
+'\" 
+'\" RCS: @(#) $Id: Load.3,v 1.1 2010/04/04 15:03:07 dkf Exp $
+'\" 
+.so man.macros
+.TH Load 3 8.6 Tcl "Tcl Library Procedures"
+.BS
+.SH NAME
+Tcl_LoadFile, Tcl_FindSymbol \- platform-independent dynamic library loading
+.SH SYNOPSIS
+.nf
+\fB#include <tcl.h>\fR
+.sp
+int
+Tcl_LoadFile(interp, pathPtr, symbols, flags, procPtrs, loadHandlePtr)
+.sp
+void *
+Tcl_FindSymbol(interp, loadHandle, symbol)
+.SH ARGUMENTS
+.AS Tcl_LoadHandle *loadHandlePtr out
+.AP Tcl_Interp *interp in
+Interpreter to use for reporting error messages.
+.AP Tcl_Obj *pathPtr in
+The name of the file to load. If it is a single name, the library search path
+of the current environment will be used to resolve it.
+.AP "const char" *symbols[] in
+Array of names of symbols to be resolved during the load of the library, or
+NULL if no symbols are to be resolved. If an array is given, the last entry in
+the array must be NULL.
+.AP int flags in
+Reserved for future expansion. Must be 0.
+.AP void *procPtrs out
+Points to an array that will hold the addresses of the functions described in
+the \fIsymbols\fR argument. Should be NULL if no symbols are to be resolved.
+.AP Tcl_LoadHandle *loadHandlePtr out
+Points to a variable that will hold the handle to the abstract token
+describing the library that has been loaded.
+.AP Tcl_LoadHandle loadHandle
+Abstract token describing the library to look up a symbol in.
+.AP "const char" *symbol in
+The name of the symbol to look up.
+.BE
+.SH DESCRIPTION
+.PP
+\fBTcl_LoadFile\fR loads a file from the filesystem (including potentially any
+virtual filesystem that has been installed) and provides a handle to it that
+may be used in further operations. The \fIsymbols\fR array, if non-NULL,
+supplies a set of names of symbols (typically functions) that must be resolved
+from the library and which will be stored in the array indicated by
+\fIprocPtrs\fR. If any of the symbols is not resolved, the loading of the file
+will fail with an error message left in the interpreter (if that is non-NULL).
+The result of \fBTcl_LoadFile\fR is a standard Tcl error code. The library may
+be unloaded with \fBTcl_FSUnloadFile\fR.
+.PP
+\fBTcl_FindSymbol\fR locates a symbol in a loaded library and returns it. If
+the symbol cannot be found, it returns NULL and sets an error message in the
+given \fIinterp\fR (if that is non-NULL). Note that it is unsafe to use this
+operation on a handle that has been passed to \fBTcl_FSUnloadFile\fR.
+.SH "SEE ALSO"
+Tcl_FSLoad(3), Tcl_FSUnload(3), load(n), unload(n)
+.SH KEYWORDS
+binary code, loading, shared library
+'\" Local Variables:
+'\" mode: nroff
+'\" fill-column: 78
+'\" End: