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diff --git a/doc/SetResult.3 b/doc/SetResult.3 deleted file mode 100644 index 1fed065..0000000 --- a/doc/SetResult.3 +++ /dev/null @@ -1,225 +0,0 @@ -'\" -'\" Copyright (c) 1989-1993 The Regents of the University of California. -'\" Copyright (c) 1994-1997 Sun Microsystems, Inc. -'\" -'\" See the file "license.terms" for information on usage and redistribution -'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES. -'\" -'\" RCS: @(#) $Id: SetResult.3,v 1.3 1999/03/10 05:52:45 stanton Exp $ -'\" -.so man.macros -.TH Tcl_SetResult 3 7.5 Tcl "Tcl Library Procedures" -.BS -.SH NAME -Tcl_SetObjResult, Tcl_GetObjResult, Tcl_SetResult, Tcl_GetStringResult, Tcl_AppendResult, Tcl_AppendResultVA, Tcl_AppendElement, Tcl_ResetResult \- manipulate Tcl result -.SH SYNOPSIS -.nf -\fB#include <tcl.h>\fR -.sp -\fBTcl_SetObjResult\fR(\fIinterp, objPtr\fR) -.sp -Tcl_Obj * -\fBTcl_GetObjResult\fR(\fIinterp\fR) -.sp -\fBTcl_SetResult\fR(\fIinterp, string, freeProc\fR) -.sp -char * -\fBTcl_GetStringResult\fR(\fIinterp\fR) -.sp -\fBTcl_AppendResult\fR(\fIinterp, string, string, ... , \fB(char *) NULL\fR) -.sp -\fBTcl_AppendResultVA\fR(\fIinterp, argList\fR) -.sp -\fBTcl_AppendElement\fR(\fIinterp, string\fR) -.sp -\fBTcl_ResetResult\fR(\fIinterp\fR) -.sp -\fBTcl_FreeResult\fR(\fIinterp\fR) -.SH ARGUMENTS -.AS Tcl_FreeProc freeProc -.AP Tcl_Interp *interp out -Interpreter whose result is to be modified or read. -.AP Tcl_Obj *objPtr in -Object value to become result for \fIinterp\fR. -.AP char *string in -String value to become result for \fIinterp\fR or to be -appended to the existing result. -.AP Tcl_FreeProc *freeProc in -Address of procedure to call to release storage at -\fIstring\fR, or \fBTCL_STATIC\fR, \fBTCL_DYNAMIC\fR, or -\fBTCL_VOLATILE\fR. -.AP va_list argList in -An argument list which must have been initialised using -\fBTCL_VARARGS_START\fR, and cleared using \fBva_end\fR. -.BE - -.SH DESCRIPTION -.PP -The procedures described here are utilities for manipulating the -result value in a Tcl interpreter. -The interpreter result may be either a Tcl object or a string. -For example, \fBTcl_SetObjResult\fR and \fBTcl_SetResult\fR -set the interpreter result to, respectively, an object and a string. -Similarly, \fBTcl_GetObjResult\fR and \fBTcl_GetStringResult\fR -return the interpreter result as an object and as a string. -The procedures always keep the string and object forms -of the interpreter result consistent. -For example, if \fBTcl_SetObjResult\fR is called to set -the result to an object, -then \fBTcl_GetStringResult\fR is called, -it will return the object's string value. -.PP -\fBTcl_SetObjResult\fR -arranges for \fIobjPtr\fR to be the result for \fIinterp\fR, -replacing any existing result. -The result is left pointing to the object -referenced by \fIobjPtr\fR. -\fIobjPtr\fR's reference count is incremented -since there is now a new reference to it from \fIinterp\fR. -The reference count for any old result object -is decremented and the old result object is freed if no -references to it remain. -.PP -\fBTcl_GetObjResult\fR returns the result for \fIinterp\fR as an object. -The object's reference count is not incremented; -if the caller needs to retain a long-term pointer to the object -they should use \fBTcl_IncrRefCount\fR to increment its reference count -in order to keep it from being freed too early or accidently changed. -.PP -\fBTcl_SetResult\fR -arranges for \fIstring\fR to be the result for the current Tcl -command in \fIinterp\fR, replacing any existing result. -The \fIfreeProc\fR argument specifies how to manage the storage -for the \fIstring\fR argument; -it is discussed in the section -\fBTHE TCL_FREEPROC ARGUMENT TO TCL_SETRESULT\fR below. -If \fIstring\fR is \fBNULL\fR, then \fIfreeProc\fR is ignored -and \fBTcl_SetResult\fR -re-initializes \fIinterp\fR's result to point to an empty string. -.PP -\fBTcl_GetStringResult\fR returns the result for \fIinterp\fR as an string. -If the result was set to an object by a \fBTcl_SetObjResult\fR call, -the object form will be converted to a string and returned. -If the object's string representation contains null bytes, -this conversion will lose information. -For this reason, programmers are encouraged to -write their code to use the new object API procedures -and to call \fBTcl_GetObjResult\fR instead. -.PP -\fBTcl_ResetResult\fR clears the result for \fIinterp\fR -and leaves the result in its normal empty initialized state. -If the result is an object, -its reference count is decremented and the result is left -pointing to an unshared object representing an empty string. -If the result is a dynamically allocated string, its memory is free*d -and the result is left as a empty string. -\fBTcl_ResetResult\fR also clears the error state managed by -\fBTcl_AddErrorInfo\fR, \fBTcl_AddObjErrorInfo\fR, -and \fBTcl_SetErrorCode\fR. - -.SH OLD STRING PROCEDURES -.PP -Use of the following procedures is deprecated -since they manipulate the Tcl result as a string. -Procedures such as \fBTcl_SetObjResult\fR -that manipulate the result as an object -can be significantly more efficient. -.PP -\fBTcl_AppendResult\fR makes it easy to build up Tcl results in pieces. -It takes each of its \fIstring\fR arguments and appends them in order -to the current result associated with \fIinterp\fR. -If the result is in its initialized empty state (e.g. a command procedure -was just invoked or \fBTcl_ResetResult\fR was just called), -then \fBTcl_AppendResult\fR sets the result to the concatenation of -its \fIstring\fR arguments. -\fBTcl_AppendResult\fR may be called repeatedly as additional pieces -of the result are produced. -\fBTcl_AppendResult\fR takes care of all the -storage management issues associated with managing \fIinterp\fR's -result, such as allocating a larger result area if necessary. -It also converts the current interpreter result from an object -to a string, if necessary, before appending the argument strings. -Any number of \fIstring\fR arguments may be passed in a single -call; the last argument in the list must be a NULL pointer. -.PP -\fBTcl_AppendResultVA\fR is the same as \fBTcl_AppendResult\fR except that -instead of taking a variable number of arguments it takes an argument list. -.PP -\fBTcl_AppendElement\fR is similar to \fBTcl_AppendResult\fR in -that it allows results to be built up in pieces. -However, \fBTcl_AppendElement\fR takes only a single \fIstring\fR -argument and it appends that argument to the current result -as a proper Tcl list element. -\fBTcl_AppendElement\fR adds backslashes or braces if necessary -to ensure that \fIinterp\fR's result can be parsed as a list and that -\fIstring\fR will be extracted as a single element. -Under normal conditions, \fBTcl_AppendElement\fR will add a space -character to \fIinterp\fR's result just before adding the new -list element, so that the list elements in the result are properly -separated. -However if the new list element is the first in a list or sub-list -(i.e. \fIinterp\fR's current result is empty, or consists of the -single character ``{'', or ends in the characters `` {'') then no -space is added. -.PP -\fBTcl_FreeResult\fR performs part of the work -of \fBTcl_ResetResult\fR. -It frees up the memory associated with \fIinterp\fR's result. -It also sets \fIinterp->freeProc\fR to zero, but doesn't -change \fIinterp->result\fR or clear error state. -\fBTcl_FreeResult\fR is most commonly used when a procedure -is about to replace one result value with another. - -.SH DIRECT ACCESS TO INTERP->RESULT IS DEPRECATED -.PP -It used to be legal for programs to -directly read and write \fIinterp->result\fR -to manipulate the interpreter result. -Direct access to \fIinterp->result\fR is now strongly deprecated -because it can make the result's string and object forms inconsistent. -Programs should always read the result -using the procedures \fBTcl_GetObjResult\fR or \fBTcl_GetStringResult\fR, -and write the result using \fBTcl_SetObjResult\fR or \fBTcl_SetResult\fR. - -.SH THE TCL_FREEPROC ARGUMENT TO TCL_SETRESULT -.PP -\fBTcl_SetResult\fR's \fIfreeProc\fR argument specifies how -the Tcl system is to manage the storage for the \fIstring\fR argument. -If \fBTcl_SetResult\fR or \fBTcl_SetObjResult\fR are called -at a time when \fIinterp\fR holds a string result, -they do whatever is necessary to dispose of the old string result -(see the \fBTcl_Interp\fR manual entry for details on this). -.PP -If \fIfreeProc\fR is \fBTCL_STATIC\fR it means that \fIstring\fR -refers to an area of static storage that is guaranteed not to be -modified until at least the next call to \fBTcl_Eval\fR. -If \fIfreeProc\fR -is \fBTCL_DYNAMIC\fR it means that \fIstring\fR was allocated with a call -to \fBTcl_Alloc\fR and is now the property of the Tcl system. -\fBTcl_SetResult\fR will arrange for the string's storage to be -released by calling \fBTcl_Free\fR when it is no longer needed. -If \fIfreeProc\fR is \fBTCL_VOLATILE\fR it means that \fIstring\fR -points to an area of memory that is likely to be overwritten when -\fBTcl_SetResult\fR returns (e.g. it points to something in a stack frame). -In this case \fBTcl_SetResult\fR will make a copy of the string in -dynamically allocated storage and arrange for the copy to be the -result for the current Tcl command. -.PP -If \fIfreeProc\fR isn't one of the values \fBTCL_STATIC\fR, -\fBTCL_DYNAMIC\fR, and \fBTCL_VOLATILE\fR, then it is the address -of a procedure that Tcl should call to free the string. -This allows applications to use non-standard storage allocators. -When Tcl no longer needs the storage for the string, it will -call \fIfreeProc\fR. \fIFreeProc\fR should have arguments and -result that match the type \fBTcl_FreeProc\fR: -.CS -typedef void Tcl_FreeProc(char *\fIblockPtr\fR); -.CE -When \fIfreeProc\fR is called, its \fIblockPtr\fR will be set to -the value of \fIstring\fR passed to \fBTcl_SetResult\fR. - -.SH "SEE ALSO" -Tcl_AddErrorInfo, Tcl_CreateObjCommand, Tcl_SetErrorCode, Tcl_Interp - -.SH KEYWORDS -append, command, element, list, object, result, return value, interpreter |