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heap32(1) [mojave man page]

heap(1) 						    BSD General Commands Manual 						   heap(1)

NAME
heap -- List all the malloc-allocated buffers in the process's heap SYNOPSIS
heap [-s | -sortBySize] [-z | -zones] [-guessNonObjects] [-sumObjectFields] [-showSizes] [-addresses all | <classes-pattern>] [-noContent] pid | partial-executable-name | memory-graph-file DESCRIPTION
heap lists the objects currently allocated on the heap of the specified process, as well as summary data. Objects are categorized by class name, type (Objective-C, C++, or CFType), and binary image. C++ objects are identified by the vtable referenced from the start of the object, so with multiple inheritance this may not give the precise class of the object. The binary image identified for a class is the image which implements the class, not necessarily the binary image which caused the objects to be allocated at runtime, or which "owns" those objects. heap requires one argument -- either the process ID or the full or partial executable name of the process to examine, or the pathname of a memory graph file generated by leaks or the Xcode Memory Graph Debugger. The following options are available: -s | -sortBySize Sort output by total size of class instances, rather than by count. -z | -zones Show the output separated out into the different malloc zones, instead of an aggregated summary of all zones. -guessNonObjects Look through the memory contents of each Objective-C object to find pointers to malloc'ed blocks (non-objects), such as the variable array hanging from an NSArray. These referenced blocks of memory are identified as their offset from the start of the object (say "__NSCFArray[12]"). The count, number of bytes, and average size of memory blocks referenced from each different object offset loca- tion are listed in the output. -sumObjectFields Do the same analysis as with the -guessNonObjects option, but add the sizes of those referenced non-object fields into the entries for the corresponding objects. -showSizes Show the distribution of each malloc size for each object, instead of summing and averaging the sizes in a single entry. -addresses all | <classes-pattern> Print the addresses of all malloc blocks found on the heap in ascending address order, or the addresses of those objects whose full class name is matched by the regular expression <classes-pattern>. The string "all" indicates that the addresses of all blocks (both objects and non-objects) should be printed. The <classes-pattern> regular expression is interpreted as an extended (modern) regular expression as described by the re_format(7) manual page. Note that toll-free-bridged CoreFoundation and Foundation classes have the "__NSCF" prefix rather than just "NS" or "CF". Examples of valid classes-patterns include: __NSCFString 'NS.*' '__NSCFString|__NSCFArray' '.*(String|Array)' -noContent Do not show object content in -addresses mode. SEE ALSO
malloc(3), leaks(1), malloc_history(1), stringdups(1), vmmap(1), DevToolsSecurity(1) The Xcode developer tools also include Instruments, a graphical application that can give information similar to that provided by heap. The Allocations instrument graphically displays dynamic, real-time information about the object and memory use in an application, including back- traces of where the allocations occurred. The Leaks instrument performs memory leak analysis. BSD
April 26, 2018 BSD

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stringdups(1)						    BSD General Commands Manual 					     stringdups(1)

NAME
stringdups -- Identify duplicate strings or other objects in malloc blocks of a target process SYNOPSIS
stringdups [-minimumCount count] [-stringsOnly] [-nostacks] [-callTrees] [-invertCallTrees] pid | partial-executable-name | memory-graph-file DESCRIPTION
stringdups examines the content of malloc blocks in the specified target process. For all blocks which have the same content, it shows a line with the number of such blocks, their total allocated size (the total size in the malloc heap, not just the specific size of their con- tent), and the average allocated size. stringdups requires one argument -- either the process ID or the full or partial executable name of the process to examine, or the pathname of a memory graph file generated by leaks. When generating a memory graph with leaks for use with stringdups it is necessary to use the -fullContent argument to include labels describing the contents of memory. If the MallocStackLogging environment variable was set when the target process was launched, stringdups also displays stack backtraces or call trees showing where all the blocks with a particular grouping of content were allocated. stringdups gathers the content of blocks of various types including: o C strings (composed of UTF8 characters, null terminated, of any length) o Pascal strings (composed of UTF8 characters with length byte at start, no longer than 255 characters, not necessarily null terminated) o NSString of all types (immutable, mutable, UTF8, Unicode). Malloc blocks which are the storage blocks for non-inline or mutable NSString's are listed separately. The string content is shown for both but the block sizes accurately show what is allocated in the mal- loc heap for that particular chunk of storage. o NSDate o NSNumber o NSPathStore2 (Cocoa's representation of file paths) o __NSMallocBlock__ For these, stringdups shows the symbol name of the code block (^) that this storage is associated with. If debug information is available, the source path and line number of the code block are also shown. o item counts for collection classes such as NSArray, NSSet, and NSDictionary OPTIONS
-minimumCount count Only print information for object descriptions which appear at least count times in the target process. The default minimum count is 2. To see all strings in the target process, use 1 or use 'heap <pid> -addresses all'. -stringsOnly Only print information for objects that have string content such as C or Pascal strings, or NSString. -nostacks Do not print stack backtraces or call trees even if the target process has the MallocStackLogging environment variable set. -callTrees If stack backtraces are available, then by default all the object descriptions for a particular stack backtrace are con- solidated together. However if this argument is passed then the output is consolidated by each particular string and a call tree is displayed showing the allocation backtraces of all occurrences of objects with that description. This out- put can be very lengthy if minimumCount is a low value, because the same call tree may be displayed many times. -invertCallTrees Same as except that the call trees are printed from hottest to coldest stack frame, so the leaf malloc call appears first. SEE ALSO
heap(1), leaks(1), malloc_history(1), vmmap(1), DevToolsSecurity(1) BSD
July 2, 2016 BSD

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