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diff --git a/doc/memory.n b/doc/memory.n new file mode 100644 index 0000000..4815ec4 --- /dev/null +++ b/doc/memory.n @@ -0,0 +1,82 @@ +'\" +'\" Copyright (c) 1992-1999 by Karl Lehenbauer and Mark Diekhans +'\" Copyright (c) 2000 by Scriptics Corporation. +'\" All rights reserved. +'\" +'\" RCS: @(#) $Id: memory.n,v 1.1 2000/04/27 01:47:00 ericm Exp $ +'\" +.so man.macros +.TH memory n 8.1 Tcl "Tcl Built-In Commands" +.BS +.SH NAME +memory \- Control Tcl memory debugging capabilities. +.SH SYNOPSIS +\fBmemory \fIoption \fR?\fIarg arg ...\fR? + +.SH DESCRIPTION +.PP +The \fBmemory\fR command gives the Tcl developer control of Tcl's memory +debugging capabilities. The memory command has several suboptions, which are +described below. It is only available when Tcl has been compiled with +memory debugging enabled (when \fBTCL_MEM_DEBUG\fR is defined at +compile time). +.TP +\fBmemory info\fR +Produces a report containing the total allocations and frees since +Tcl began, the current packets allocated (the current +number of calls to \fBckalloc\fR not met by a corresponding call +to \fBckfree\fR), the current bytes allocated, and the maximum number +of packets and bytes allocated. +.TP +\fBmemory trace [on|off]\fR +.br +Turns memory tracing on or off. When memory tracing is on, every call +to \fBckalloc\fR causes a line of trace information to be written to +\fIstderr\fR, consisting of the word \fIckalloc\fR, followed by the +address returned, the amount of memory allocated, and the C filename +and line number of the code performing the allocation. For example: +.CS +ckalloc 40e478 98 tclProc.c 1406 +.CE +Calls to \fBckfree\fR are traced in the same manner. +.TP +\fBmemory validate [on|off]\fR +Turns memory validation on or off. When memory validation is enabled, +on every call to \fBckalloc\fR or \fBckfree\fR, the guard zones are +checked for every piece of memory currently in existence that was +allocated by \fBckalloc\fR. This has a large performance impact and +should only be used when overwrite problems are strongly suspected. +The advantage of enabling memory validation is that a guard zone +overwrite can be detected on the first call to \fBckalloc\fR or +\fBckfree\fR after the overwrite occurred, rather than when the +specific memory with the overwritten guard zone(s) is freed, which may +occur long after the overwrite occurred. +.TP +\fBmemory trace_on_at_malloc\fR \fIcount\fR +Enable memory tracing after \fIcount\fR \fBckalloc\fR's have been performed. +For example, if you enter \fBmemory trace_on_at_malloc 100\fR, +after the 100th call to \fBckalloc\fR, memory trace information will begin +being displayed for all allocations and frees. Since there can be a lot +of memory activity before a problem occurs, judicious use of this option +can reduce the slowdown caused by tracing (and the amount of trace information +produced), if you can identify a number of allocations that occur before +the problem sets in. The current number of memory allocations that have +occurred since Tcl started is printed on a guard zone failure. +.TP +\fBmemory break_on_malloc\fR \fIcount\fR +After the \fBcount\fR allocations have been performed, \fBckalloc\fR's +output a message to this effect and that it is now attempting to enter +the C debugger. Tcl will then issue a \fISIGINT\fR signal against itself. +If you are running Tcl under a C debugger, it should then enter the debugger +command mode. +.TP +\fB memory display\fR \fIfile\fR +Write a list of all currently allocated memory to the specified file. + +.SH SEE ALSO +ckalloc, ckfree, Tcl_ValidateAllMemory, Tcl_DumpActiveMemory, TCL_MEM_DEBUG + +.SH KEYWORDS +memory, debug + + |