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gprof Command Summary

After you have a profile data file `gmon.out', you can run gprof to interpret the information in it. The gprof program prints a flat profile and a call graph on standard output. Typically you would redirect the output of gprof into a file with `>'.

You run gprof like this:

gprof options [executable-file [profile-data-files...]] [> outfile]

Here square-brackets indicate optional arguments.

If you omit the executable file name, the file `a.out' is used. If you give no profile data file name, the file `gmon.out' is used. If any file is not in the proper format, or if the profile data file does not appear to belong to the executable file, an error message is printed.

You can give more than one profile data file by entering all their names after the executable file name; then the statistics in all the data files are summed together.

The following options may be used to selectively include or exclude functions in the output:

-a
The `-a' option causes gprof to suppress the printing of statically declared (private) functions. (These are functions whose names are not listed as global, and which are not visible outside the file/function/block where they were defined.) Time spent in these functions, calls to/from them, etc, will all be attributed to the function that was loaded directly before it in the executable file. This option affects both the flat profile and the call graph.
-D
The `-D' option causes gprof to ignore symbols which are not known to be functions. This option will give more accurate profile data on systems where it is supported (Solaris and HPUX for example).
-e function_name
The `-e function' option tells gprof to not print information about the function function_name (and its children...) in the call graph. The function will still be listed as a child of any functions that call it, but its index number will be shown as `[not printed]'. More than one `-e' option may be given; only one function_name may be indicated with each `-e' option.
-E function_name
The -E function option works like the -e option, but time spent in the function (and children who were not called from anywhere else), will not be used to compute the percentages-of-time for the call graph. More than one `-E' option may be given; only one function_name may be indicated with each `-E' option.
-f function_name
The `-f function' option causes gprof to limit the call graph to the function function_name and its children (and their children...). More than one `-f' option may be given; only one function_name may be indicated with each `-f' option.
-F function_name
The `-F function' option works like the -f option, but only time spent in the function and its children (and their children...) will be used to determine total-time and percentages-of-time for the call graph. More than one `-F' option may be given; only one function_name may be indicated with each `-F' option. The `-F' option overrides the `-E' option.
-k from... to...
The `-k' option allows you to delete from the profile any arcs from routine from to routine to.
-v
The `-v' flag causes gprof to print the current version number, and then exit.
-z
If you give the `-z' option, gprof will mention all functions in the flat profile, even those that were never called, and that had no time spent in them. This is useful in conjunction with the `-c' option for discovering which routines were never called.

The order of these options does not matter.

Note that only one function can be specified with each -e, -E, -f or -F option. To specify more than one function, use multiple options. For example, this command:

gprof -e boring -f foo -f bar myprogram > gprof.output

lists in the call graph all functions that were reached from either foo or bar and were not reachable from boring.

There are a few other useful gprof options:

-b
If the `-b' option is given, gprof doesn't print the verbose blurbs that try to explain the meaning of all of the fields in the tables. This is useful if you intend to print out the output, or are tired of seeing the blurbs.
-c
The `-c' option causes the static call-graph of the program to be discovered by a heuristic which examines the text space of the object file. Static-only parents or children are indicated with call counts of `0'.
-d num
The `-d num' option specifies debugging options.
-s
The `-s' option causes gprof to summarize the information in the profile data files it read in, and write out a profile data file called `gmon.sum', which contains all the information from the profile data files that gprof read in. The file `gmon.sum' may be one of the specified input files; the effect of this is to merge the data in the other input files into `gmon.sum'. See section Statistical Inaccuracy of gprof Output. Eventually you can run gprof again without `-s' to analyze the cumulative data in the file `gmon.sum'.
-T
The `-T' option causes gprof to print its output in "traditional" BSD style.
--function-ordering
The `--function-ordering' option causes gprof to print a suggested function ordering for the program based on profiling data. This option suggests an ordering which may improve paging, tlb and cache behavior for the program on systems which support arbitrary ordering of functions in an executable. The exact details of how to force the linker to place functions in a particular order is system dependent and out of the scope of this manual.
--file-ordering map_file
The `--file-ordering' option causes gprof to print a suggested .o link line ordering for the program based on profiling data. This option suggests an ordering which may improve paging, tlb and cache behavior for the program on systems which do not support arbitrary ordering of functions in an executable. Use of the `-a' argument is highly recommended with this option. The map_file argument is a pathname to a file which provides function name to object file mappings. The format of the file is similar to the output of the program nm.
c-parse.o:00000000 T yyparse
c-parse.o:00000004 C yyerrflag
c-lang.o:00000000 T maybe_objc_method_name
c-lang.o:00000000 T print_lang_statistics
c-lang.o:00000000 T recognize_objc_keyword
c-decl.o:00000000 T print_lang_identifier
c-decl.o:00000000 T print_lang_type
...

GNU nm `--extern-only' `--defined-only' `-v' `--print-file-name' can be used to create map_file.

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