mksizes

早期freebsd实现

#!/usr/local/bin/perl

($iam = $0) =~ s%.*/%%;
$tmp = "$iam.$$";
open (CODE,">$tmp.c") || die "$iam: cannot create $tmp.c: $!\n";

$mask = q/printf ("$sizeof{'%s'} = %d;\n"/; 

# write C program
select(CODE);

print <<EO_C_PROGRAM;
#include <sys/param.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <net/if_arp.h>
#include <net/if.h>
#include <net/route.h>
#include <sys/ioctl.h>

main() {
EO_C_PROGRAM

while ( <> ) {
    chop;
    printf "\t%s, \n\t\t\"%s\", sizeof(%s));\n", $mask, $_,$_;
}

print "\n}\n";

close CODE;

# compile C program

select(STDOUT);

system "cc $tmp.c -o $tmp";
die "couldn't compile $tmp.c" if $?;
system "./$tmp"; 	   
die "couldn't run $tmp" if $?;

unlink "$tmp.c", $tmp;