ncurses 6.4 - patch 20231001

[ncurses.git] / man / curs_trace.3x

diff --git a/man/curs_trace.3x b/man/curs_trace.3x
index 00e7bd63165f1fe908d07f2bf2cf143e80ffef6f..f793267a89a032dfcd02e5bfb563f130e22e8399 100644 (file)
--- a/man/curs_trace.3x
+++ b/man/curs_trace.3x
@@ -1,5 +1,6 @@
 .\"***************************************************************************
 .\"***************************************************************************

-.\" Copyright (c) 2000-2010,2015 Free Software Foundation, Inc.              *
+.\" Copyright 2019-2022,2023 Thomas E. Dickey                                *
+.\" Copyright 2000-2016,2017 Free Software Foundation, Inc.                  *

 .\"                                                                          *
 .\" Permission is hereby granted, free of charge, to any person obtaining a  *
 .\" copy of this software and associated documentation files (the            *
 .\"                                                                          *
 .\" Permission is hereby granted, free of charge, to any person obtaining a  *
 .\" copy of this software and associated documentation files (the            *


@@ -26,83 +27,116 @@
 .\" authorization.                                                           *
 .\"***************************************************************************
 .\"
 .\" authorization.                                                           *
 .\"***************************************************************************
 .\"

-.\" $Id: curs_trace.3x,v 1.13 2015/07/20 22:54:44 tom Exp $
+.\" $Id: curs_trace.3x,v 1.39 2023/09/30 21:38:11 tom Exp $
+.TH curs_trace 3X 2023-09-30 "ncurses 6.4" "Library calls"
+.ie \n(.g .ds `` \(lq
+.el       .ds `` ``
+.ie \n(.g .ds '' \(rq
+.el       .ds '' ''

 .de bP
 .de bP

-.IP \(bu 4
+.ie n  .IP \(bu 4
+.el    .IP \(bu 2

 ..
 ..

-.TH curs_trace 3X ""
-.na
-.hy 0

 .SH NAME
 .SH NAME

-\fB_tracef\fR,
-\fB_tracedump\fR,
-\fB_traceattr\fR,
-\fB_traceattr2\fR,
-\fB_nc_tracebits\fR,
-\fB_tracecchar_t\fR,
-\fB_tracecchar_t2\fR,
-\fB_tracechar\fR,
-\fB_tracechtype\fR,
-\fB_tracechtype2\fR,
-\fB_tracemouse\fR,
-\fBtrace\fR \- \fBcurses\fR debugging routines
-.ad
-.hy
+\fB\%curses_trace\fP,
+\fB\%trace\fP,
+\fB\%_tracef\fP,
+\fB\%_traceattr\fP,
+\fB\%_traceattr2\fP,
+\fB\%_tracecchar_t\fP,
+\fB\%_tracecchar_t2\fP,
+\fB\%_tracechar\fP,
+\fB\%_tracechtype\fP,
+\fB\%_tracechtype2\fP,
+\fB\%_nc_tracebits\fP,
+\fB\%_tracedump\fP,
+\fB\%_tracemouse\fP \-
+\fIcurses\fR debugging routines

 .SH SYNOPSIS
 .SH SYNOPSIS

-\fB#include <curses.h>\fR
-.sp
-\fBvoid _tracef(const char *\fP\fIformat\fP\fB, ...);\fR
-.br
-\fBvoid _tracedump(const char *\fP\fIlabel\fP\fB, WINDOW *\fP\fIwin\fP\fB);\fR
-.br
-\fBchar *_traceattr(attr_t \fP\fIattr\fP\fB);\fR
-.br
-\fBchar *_traceattr2(int \fP\fIbuffer\fP\fB, chtype \fP\fIch\fP\fB);\fR
-.br
-\fBchar *_nc_tracebits(void);\fR
-.br
-\fBchar * _tracecchar_t(const cchar_t *\fP\fIstring\fP\fB);\fR
-.br
-\fBchar * _tracecchar_t2(int \fP\fIbuffer\fP\fB, const cchar_t *\fP\fIstring\fP\fB);\fR
-.br
-\fBchar *_tracechar(int \fP\fIch\fP\fB);\fR
-.br
-\fBchar *_tracechtype(chtype \fP\fIch\fP\fB);\fR
-.br
-\fBchar *_tracechtype2(int \fP\fIbuffer\fP\fB, chtype \fP\fIch\fP\fB);\fR
-.br
-\fBchar *_tracemouse(const MEVENT *\fP\fIevent\fP\fB);\fR
-.br
-\fBvoid trace(const unsigned int \fP\fIparam\fP\fB);\fR
+.nf
+\fB#include <curses.h>\fP
+.PP
+\fBunsigned curses_trace(const unsigned \fIparam\fB);\fR
+.PP
+\fBvoid _tracef(const char *\fIformat\fB, ...);\fR
+.PP
+\fBchar *_traceattr(attr_t \fIattr\fB);\fR
+\fBchar *_traceattr2(int \fIbuffer\fB, chtype \fIch\fB);\fR
+\fBchar *_tracecchar_t(const cchar_t *\fIstring\fB);\fR
+\fBchar *_tracecchar_t2(int \fIbuffer\fB, const cchar_t *\fIstring\fB);\fR
+\fBchar *_tracechar(int \fIch\fB);\fR
+\fBchar *_tracechtype(chtype \fIch\fB);\fR
+\fBchar *_tracechtype2(int \fIbuffer\fB, chtype \fIch\fB);\fR
+.PP
+\fBvoid _tracedump(const char *\fIlabel\fB, WINDOW *\fIwin\fB);\fR
+\fBchar *_nc_tracebits(void);\fP
+\fBchar *_tracemouse(const MEVENT *\fIevent\fB);\fR
+.PP
+/* deprecated */
+\fBvoid trace(const unsigned int \fIparam\fB);\fR
+.fi

 .SH DESCRIPTION
 .SH DESCRIPTION

-The \fBtrace\fR routines are used for debugging the ncurses libraries,
+The \fIcurses trace\fP routines are used for debugging the ncurses libraries,

 as well as applications which use the ncurses libraries.
 as well as applications which use the ncurses libraries.

-These functions are normally available only with the debugging library
-e.g., \fIlibncurses_g.a\fR, but may be compiled into any model (shared, static,
-profile) by defining the symbol \fBTRACE\fR.
-Additionally, some functions are only available with the wide-character
-configuration of the libraries.
-.PP
+Some limitations apply:
+.bP
+Aside from \fBcurses_trace\fP,
+the other functions are normally available only with the debugging library
+e.g., \fBlibncurses_g.a\fP.
+.IP
+All of the trace functions may be compiled into any model (shared, static,
+profile) by defining the symbol \fBTRACE\fP.
+.bP
+Additionally, the functions which use \fBcchar_t\fP
+are only available with the wide-character configuration of the libraries.
+.SS Functions

 The principal parts of this interface are
 .bP
 The principal parts of this interface are
 .bP

-\fBtrace\fR, which selectively enables different tracing features, and
+\fBcurses_trace\fP, which selectively enables different tracing features, and

 .bP
 .bP

-\fB_tracef\fR, which writes formatted data to the \fItrace\fR file.
+\fB_tracef\fP, which writes formatted data to the \fItrace\fP file.
+.IP
+The other functions either return a pointer to a string-area
+(allocated by the corresponding function), or return no value
+(such as \fB_tracedump\fP,
+which implements the screen dump for \fBTRACE_UPDATE\fP).
+The caller should not free these strings,
+since the allocation is reused on successive calls.
+To work around the problem of a single string-area per function,
+some use a buffer-number parameter, telling the library to allocate
+additional string-areas.

 .PP
 .PP

-Calling \fBtrace\fR with a nonzero parameter opens the file \fBtrace\fR
-in the current directory for output.
-The parameter is formed by OR'ing
-values from the list of \fBTRACE_\fP\fIxxx\fR definitions in \fB<curses.h>\fR.
+The \fBcurses_trace\fP function is always available,
+whether or not the other trace functions are available:
+.bP
+If tracing is available,
+calling \fBcurses_trace\fP with a nonzero parameter
+updates the trace mask,
+and returns the previous trace mask.
+.IP
+When the trace mask is nonzero,
+ncurses creates the file \*(``trace\*('' in the current directory for output.
+If the file already exists, no tracing is done.
+.bP
+If tracing is not available, \fBcurses_trace\fP returns zero (0).
+.SS Trace Parameter
+The trace parameter is formed by OR'ing
+values from the list of \fBTRACE_\fIxxx\fR definitions in \fB<curses.h>\fR.

 These include:
 .TP 5
 .B TRACE_DISABLE
 These include:
 .TP 5
 .B TRACE_DISABLE

-turn off tracing.
+turn off tracing by passing a zero parameter.
+.IP
+The library flushes the output file,
+but retains an open file-descriptor to the trace file
+so that it can resume tracing later if a nonzero parameter is passed
+to the \fBcurses_trace\fP function.

 .TP 5
 .B TRACE_TIMES
 trace user and system times of updates.
 .TP 5
 .B TRACE_TPUTS
 .TP 5
 .B TRACE_TIMES
 trace user and system times of updates.
 .TP 5
 .B TRACE_TPUTS

-trace tputs calls.
+trace \fBtputs\fP(3X) calls.

 .TP 5
 .B TRACE_UPDATE
 trace update actions, old & new screens.
 .TP 5
 .B TRACE_UPDATE
 trace update actions, old & new screens.


@@ -123,7 +157,7 @@ trace all curses calls.
 The parameters for each call are traced, as well as return values.
 .TP 5
 .B TRACE_VIRTPUT
 The parameters for each call are traced, as well as return values.
 .TP 5
 .B TRACE_VIRTPUT

-trace virtual character puts, i.e., calls to \fBaddch\fR.
+trace virtual character puts, i.e., calls to \fBaddch\fP.

 .TP 5
 .B TRACE_IEVENT
 trace low-level input processing, including timeouts.
 .TP 5
 .B TRACE_IEVENT
 trace low-level input processing, including timeouts.


@@ -146,26 +180,15 @@ trace changes to video attributes and colors.
 .B TRACE_MAXIMUM
 maximum trace level, enables all of the separate trace features.
 .PP
 .B TRACE_MAXIMUM
 maximum trace level, enables all of the separate trace features.
 .PP

-Some tracing features are enabled whenever the \fBtrace\fR parameter
+Some tracing features are enabled whenever the \fBcurses_trace\fP parameter

 is nonzero.
 Some features overlap.
 The specific names are used as a guideline.
 is nonzero.
 Some features overlap.
 The specific names are used as a guideline.

-.PP
-The other functions either return a pointer to a string-area
-(allocated by the corresponding function),
-or return no value (such as \fB_tracedump\fP, which implements the
-screen dump for \fBTRACE_UPDATE\fP).
-The caller should not free these
-strings, since the allocation is reused on successive calls.
-To work around the problem of a single string-area per function,
-some use a buffer-number parameter, telling the library to allocate
-additional string-areas.
-.PP
+.SS Initialization

 These functions check the \fBNCURSES_TRACE\fP environment variable,
 These functions check the \fBNCURSES_TRACE\fP environment variable,

-to set the tracing feature as if \fBtrace\fP was called:
-.RS
+to set the tracing feature as if \fBcurses_trace\fP was called:
+.RS 4

 .PP
 .PP

-.na

 filter,
 initscr,
 new_prescr,
 filter,
 initscr,
 new_prescr,


@@ -179,15 +202,74 @@ tgetent,
 use_env,
 use_extended_names,
 use_tioctl
 use_env,
 use_extended_names,
 use_tioctl

-.ad

 .RE
 .RE

+.SS Command-line Utilities
+The command-line utilities such as \fBtic\fP(1) provide a verbose option
+which extends the set of messages written using the \fBcurses_trace\fP function.
+Both of these (\fB\-v\fP and \fBcurses_trace\fP)
+use the same variable (\fB_nc_tracing\fP),
+which determines the messages which are written.
+.PP
+Because the command-line utilities may call initialization functions
+such as \fBsetupterm\fP, \fBtgetent\fP or \fBuse_extended_names\fP,
+some of their debugging output may be directed to the \fItrace\fP file
+if the \fBNCURSES_TRACE\fP environment variable is set:
+.bP
+messages produced in the utility are written to the standard error.
+.bP
+messages produced by the underlying library are written to \fItrace\fP.
+.PP
+If ncurses is built without tracing, none of the latter are produced,
+and fewer diagnostics are provided by the command-line utilities.

 .SH RETURN VALUE
 Routines which return a value are designed to be used as parameters
 .SH RETURN VALUE
 Routines which return a value are designed to be used as parameters

-to the \fB_tracef\fR routine.
+to the \fB_tracef\fP routine.

 .SH PORTABILITY
 These functions are not part of the XSI interface.
 Some other curses implementations are known to
 .SH PORTABILITY
 These functions are not part of the XSI interface.
 Some other curses implementations are known to

-have similar, undocumented features,
-but they are not compatible with ncurses.
+have similar features,
+but they are not compatible with ncurses:
+.bP
+SVr4 provided \fBtraceon\fP and \fBtraceoff\fP,
+to control whether debugging information was written
+to the \*(``trace\*('' file.
+While the functions were always available,
+this feature was only enabled
+if \fBDEBUG\fP was defined when building the library.
+.IP
+The SVr4 tracing feature is undocumented.
+.bP
+PDCurses provides \fBtraceon\fP and \fBtraceoff\fP,
+which (like SVr4) are always available,
+and enable tracing
+to the \*(``trace\*('' file
+only when a debug-library is built.
+.IP
+PDCurses has a short description of these functions,
+with a note that they are not present in X/Open Curses,
+ncurses or NetBSD.
+It does not mention SVr4,
+but the functions' inclusion in a header file section
+labeled \*(``Quasi-standard\*('' hints at the origin.
+.bP
+NetBSD does not provide functions for enabling/disabling traces.
+It uses environment variables
+\fBCURSES_TRACE_MASK\fP and
+\fBCURSES_TRACE_FILE\fP to determine what is traced,
+and where the results are written.
+This is available only when a debug-library is built.
+.IP
+The NetBSD tracing feature is undocumented.
+.PP
+A few ncurses functions are not provided when symbol versioning is used:
+.RS 4
+.PP
+_nc_tracebits,
+_tracedump,
+_tracemouse
+.RE
+.PP
+The original \fBtrace\fP routine was deprecated because
+it often conflicted with application names.

 .SH SEE ALSO
 .SH SEE ALSO

-\fBcurses\fR(3X).
+\fB\%curses\fP(3X)