unifdef(1)

NAME

unifdef − remove preprocessor lines

SYNOPSIS

unifdef [-clt] [[-D sym] [-U sym] [-iD sym] [-iU sym]] ... [file]

DESCRIPTION

unifdef simulates some of the actions of cpp in interpreting C language preprocessor command lines (see cpp(1)). For unifdef, a valid preprocessor command line contains as its first character a # and one of the following keywords: ifdef, ifndef, if, else, or endif. The # character and its associated keyword must appear on the same line, but they can be separated by spaces, tabs, and commented text. When appropriate, the portions of code surrounded by and including the targeted preprocessor directives are removed, and the resultant text is written to the standard output.

Unlike cpp, unifdef does not insert included files, interpret macros, or strip comment lines. This means, among other things, that #define and #undef macros occurring within the input text are not interpreted.

Since unifdef is language-independent, it can be used for processing source files for languages other than the C language. For example, unifdef can be used on FORTRAN language source files, provided the C language preprocessor commands are used.

Options

unifdef recognizes the following command-line options:

-c Complement the normal behavior by printing only the rejected lines.

-iDsym Ignore text delimited by #ifdef sym. In other words, text that would otherwise be affected by some action is not touched when found within the context of a preprocessor command using sym.

-iUsym Ignore text delimited by #ifndef sym.

-l Replace rejected lines with blank lines in the text written to the standard output.

-t Treat the input source as plain text. C-language comment and quoting constructs are not recognized.

-Dsym Define symbol sym.

-Usym Cause symbol sym to be undefined.

RETURN VALUE

The unifdef command returns the following exit values:

0 Output is an exact copy of the input.

1 Output is not an exact copy of the input.

2 The unifdef command fails. The failure might be due to a premature EOF or to an inappropriate else, elif, or endif.

EXAMPLES

Assume file foo.f contains the following:

    PROGRAM TEST1
    INTEGER I, J
#ifdef ANSI77
    DO I=1,10
#else
    DO 100 I=1,10
#endif
    J=J+1
#if defined (DEBUG) || defined (TEST)
    PRINT *,J
#endif
#ifdef ANSI77
    ENDDO
#else
        100   CONTINUE
#endif
    END

The command sequence:

unifdef -DANSI77 -UDEBUG -DTEST foo.f > /tmp/foo.f

produces the following result in file /tmp/foo.f:

PROGRAM TEST1
INTEGER I, J
DO I=1,10
J=J+1
PRINT *,J
ENDDO
END

WARNINGS

Any symbol name defined in the file must be specified in the unifdef command line; otherwise, unifdef will ignore the line.

AUTHOR

unifdef was developed in the public domain.

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