


UNIFDEF(1)	    UNIX Programmer's Manual	       UNIFDEF(1)



NAME
     unifdef - remove ifdef'ed lines

SYNOPSIS
     unifdef [ -t -l -c -D_s_y_m -U_s_y_m -id_s_y_m -iu_s_y_m ] ...  [ file ]

DESCRIPTION
     _U_n_i_f_d_e_f is useful for removing ifdef'ed lines from a file
     while otherwise leaving the file alone.  _U_n_i_f_d_e_f is like a
     stripped-down C preprocessor: it is smart enough to deal
     with the nested ifdefs, comments, single and double quotes
     of C syntax so that it can do its job, but it doesn't do any
     including or interpretation of macros.  Neither does it
     strip out comments, though it recognizes and ignores them.
     You specify which symbols you want defined -D_s_y_m or unde-
     fined -U_s_y_m and the lines inside those ifdefs will be copied
     to the output or removed as appropriate.  The ifdef, ifndef,
     else, and endif lines associated with _s_y_m will also be
     removed.  Ifdefs involving symbols you don't specify are
     untouched and copied out along with their associated ifdef,
     else, and endif lines.  If an ifdef X occurs nested inside
     another ifdef X, then the inside ifdef is treated as if it
     were an unrecognized symbol.  If the same symbol appears in
     more than one argument, only the first occurrence is signi-
     ficant.

     The -l option causes _u_n_i_f_d_e_f to replace removed lines with
     blank lines instead of deleting them.

     If you use ifdefs to delimit non-C lines, such as comments
     or code which is under construction, then you must tell
     _u_n_i_f_d_e_f which symbols are used for that purpose so that it
     won't try to parse for quotes and comments in those ifdef'ed
     lines.  You specify that you want the lines inside certain
     ifdefs to be ignored but copied out with -id_s_y_m and -iu_s_y_m
     similar to -D_s_y_m and -U_s_y_m above.

     If you want to use _u_n_i_f_d_e_f for plain text (not C code), use
     the -t option.  This makes _u_n_i_f_d_e_f refrain from attempting
     to recognize comments and single and double quotes.

     _U_n_i_f_d_e_f copies its output to _s_t_d_o_u_t and will take its input
     from _s_t_d_i_n if no _f_i_l_e argument is given.  If the -c argument
     is specified, then the operation of _u_n_i_f_d_e_f is complemented,
     i.e. the lines that would have been removed or blanked are
     retained and vice versa.

SEE ALSO
     diff(1)

DIAGNOSTICS
     Premature EOF, inappropriate else or endif.



Printed 11/26/99	 April 29, 1985                         1






UNIFDEF(1)	    UNIX Programmer's Manual	       UNIFDEF(1)



     Exit status is 0 if output is exact copy of input, 1 if not,
     2 if trouble.

BUGS
     Does not know how to deal with _c_p_p consructs such as

	  #if  defined(X) || defined(Y)


AUTHOR
     Dave Yost












































Printed 11/26/99	 April 29, 1985                         2



