CFLOW(1,C)                  AIX Commands Reference                   CFLOW(1,C)



-------------------------------------------------------------------------------
cflow



PURPOSE

Generates a C flow graph of external references.

SYNTAX


         +------------+
cflow ---| +--------+ |--- file ---|
         +-| -d num |-+ ^        |
          ^| -r     ||  +--------+
          || -i_    ||
          || -ix    ||
          |+--------+|
          +----------+


Note:  This command is for the PS/2 only.

Note:  This command does not have MBCS support.

DESCRIPTION

The cflow command analyzes C, yacc, lex, assembler, and object files and writes
a chart of their external references to standard output.

The cflow command sends files with .y, .l, and .c suffixes to the yacc, lex,
and cpp commands for the appropriate processing.  This step is bypassed for .i
files.  The command then runs the output of this processing through the first
pass of the lint command.  It assembles files which end in .s, extracting
information from the symbol table (as it does with .o files).  From this
output, the cflow command produces a graph of external references, which it
writes to standard output.

Each line of output begins with a line number followed by sufficient tabs to
indicate the level of nesting.  Then comes the name of the global, a colon, and
its definition.  This name is normally a function not defined as external and
not beginning with an underline character (see the -i_ inclusion flag on p.
        2).  For information extracted from C source files, the definition
consists of an abstract type declaration (for example, "char*"), the name of
the source file (surrounded by angle brackets), and the line number on which
the definition was found.  Definitions extracted from object files contain the
file name and location counter under which the symbol appeared.  The cflow
command deletes leading underline characters in C-style external names.






Processed November 8, 1990        CFLOW(1,C)                                  1

CFLOW(1,C)                  AIX Commands Reference                   CFLOW(1,C)



Once the cflow command displays the definition of a name, later references to
it contain only the cflow line number where the definition may be found.  For
undefined references, the cflow command displays only <>.

If the nesting level becomes too deep to display in available space, pipe the
output from the cflow command to the pr command, using the -e flag to compress
the tab expansion to something less than every eight spaces.

Note:  Files produced by the lex and yacc command cause the reordering of line
       number declarations which can confuse the cflow command.  To get proper
       results, provide the cflow command with yacc or lex command input.

FLAGS

The cflow command recognizes the following flags:

-dnum     Sets to decimal integer num the depth at which the flow graph is cut
          off.  By default, num is a very large number.  Do not set the cutoff
          depth to a negative integer.

-ix       Includes external and static data symbols.  The default includes only
          functions.

-i_       Includes names that begin with an underline character.  The default
          excludes these functions (and corresponding data if the -ix flag is
          used).

-r        Produces an inverted listing, which shows the callers of each
          function, sorted by called function.

          In addition to these flags, the cflow command recognizes the -I, -D,
          and -U flags of the cpp command.

RELATED INFORMATION

See the following commands:  "as,"  "cc,"  "lex," "lint,"  "nm,"  "pr," and
"yacc."

See the discussion of the cflow programming tool in AIX Operating System
Programming Tools and Interfaces.















Processed November 8, 1990        CFLOW(1,C)                                  2