


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



NAME
     struct - structure Fortran programs

SYNOPSIS
     struct [ option ] ...  file

DESCRIPTION
     _S_t_r_u_c_t translates the Fortran program specified by _f_i_l_e
     (standard input default) into a Ratfor program.  Wherever
     possible, Ratfor control constructs replace the original
     Fortran.  Statement numbers appear only where still neces-
     sary.  Cosmetic changes are made, including changing Holler-
     ith strings into quoted strings and relational operators
     into symbols (.e.g. ".GT." into ">").  The output is
     appropriately indented.

     The following options may occur in any order.

     -s   Input is accepted in standard format, i.e.  comments
	  are specified by a c, C, or * in column 1, and con-
	  tinuation lines are specified by a nonzero, nonblank
	  character in column 6.  Normally input is in the form
	  accepted by _f_7_7(1)

     -i   Do not turn computed goto statements into switches.
	  (Ratfor does not turn switches back into computed goto
	  statements.)

     -a   Turn sequences of else ifs into a non-Ratfor switch of
	  the form


	  switch
	       { case pred1: code
		 case pred2: code
		 case pred3: code
		 default: code
	       }

	  The case predicates are tested in order; the code
	  appropriate to only one case is executed.  This gen-
	  eralized form of switch statement does not occur in
	  Ratfor.

     -b   Generate goto's instead of multilevel break statements.

     -n   Generate goto's instead of multilevel next statements.

     -t_n  Make the nonzero integer _n the lowest valued label in
	  the output program (default 10).

     -c_n  Increment successive labels in the output program by



Printed 11/26/99	October 22, 1996			1






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



	  the nonzero integer _n (default 1).

     -e_n  If _n is 0 (default), place code within a loop only if
	  it can lead to an iteration of the loop.  If _n is
	  nonzero, admit a small code segments to a loop if oth-
	  erwise the loop would have exits to several places
	  including the segment, and the segment can be reached
	  only from the loop.  `Small' is close to, but not equal
	  to, the number of statements in the code segment.
	  Values of n under 10 are suggested.

FILES
     /tmp/struct*
     /usr/libexec/struct/*

SEE ALSO
     f77(1)

BUGS
     Struct knows Fortran 66 syntax, but not full Fortran 77.
     If an input Fortran program contains identifiers which are
     reserved words in Ratfor, the structured version of the pro-
     gram will not be a valid Ratfor program.
     The labels generated cannot go above 32767.
     If you get a goto without a target, try -e .






























Printed 11/26/99	October 22, 1996			2



