int main(int argc, char **argv, char **env)
{
+ PERL_SYS_INIT3(&argc,&argv,&env);
my_perl = perl_alloc();
perl_construct(my_perl);
PL_exit_flags |= PERL_EXIT_DESTRUCT_END;
perl_run(my_perl);
perl_destruct(my_perl);
perl_free(my_perl);
+ PERL_SYS_TERM();
}
Notice that we don't use the C<env> pointer. Normally handed to
C<perl_parse> as its final argument, C<env> here is replaced by
-C<NULL>, which means that the current environment will be used.
+C<NULL>, which means that the current environment will be used. The macros
+PERL_SYS_INIT3() and PERL_SYS_TERM() provide system-specific tune up
+of the C runtime environment necessary to run Perl interpreters; since
+PERL_SYS_INIT3() may change C<env>, it may be more appropriate to provide
+C<env> as an argument to perl_parse().
Now compile this program (I'll call it I<interp.c>) into an executable:
int main(int argc, char **argv, char **env)
{
char *args[] = { NULL };
+ PERL_SYS_INIT3(&argc,&argv,&env);
my_perl = perl_alloc();
perl_construct(my_perl);
perl_destruct(my_perl);
perl_free(my_perl);
+ PERL_SYS_TERM();
}
where I<showtime> is a Perl subroutine that takes no arguments (that's the
STRLEN n_a;
char *embedding[] = { "", "-e", "0" };
+ PERL_SYS_INIT3(&argc,&argv,&env);
my_perl = perl_alloc();
perl_construct( my_perl );
perl_destruct(my_perl);
perl_free(my_perl);
+ PERL_SYS_TERM();
}
All of those strange functions with I<sv> in their names help convert Perl scalars to C types. They're described in L<perlguts> and L<perlapi>.
SV *text;
STRLEN n_a;
+ PERL_SYS_INIT3(&argc,&argv,&env);
my_perl = perl_alloc();
perl_construct(my_perl);
perl_parse(my_perl, NULL, 3, embedding, NULL);
PL_perl_destruct_level = 1;
perl_destruct(my_perl);
perl_free(my_perl);
+ PERL_SYS_TERM();
}
which produces the output (again, long lines have been wrapped here)
{
char *my_argv[] = { "", "power.pl" };
+ PERL_SYS_INIT3(&argc,&argv,&env);
my_perl = perl_alloc();
perl_construct( my_perl );
perl_destruct(my_perl);
perl_free(my_perl);
+ PERL_SYS_TERM();
}
#define DO_CLEAN 0
#endif
+ #define BUFFER_SIZE 1024
+
static PerlInterpreter *my_perl = NULL;
int
{
char *embedding[] = { "", "persistent.pl" };
char *args[] = { "", DO_CLEAN, NULL };
- char filename [1024];
+ char filename[BUFFER_SIZE];
int exitstatus = 0;
STRLEN n_a;
+ PERL_SYS_INIT3(&argc,&argv,&env);
if((my_perl = perl_alloc()) == NULL) {
fprintf(stderr, "no memory!");
exit(1);
if(!exitstatus) {
exitstatus = perl_run(my_perl);
- while(printf("Enter file name: ") && gets(filename)) {
+ while(printf("Enter file name: ") &&
+ fgets(filename, BUFFER_SIZE, stdin)) {
+ filename[strlen(filename)-1] = '\0'; /* strip \n */
/* call the subroutine, passing it the filename as an argument */
args[0] = filename;
call_argv("Embed::Persistent::eval_file",
PL_perl_destruct_level = 0;
perl_destruct(my_perl);
perl_free(my_perl);
+ PERL_SYS_TERM();
exit(exitstatus);
}
int main(int argc, char **argv, char **env)
{
- PerlInterpreter
- *one_perl = perl_alloc(),
- *two_perl = perl_alloc();
+ PerlInterpreter *one_perl, *two_perl;
char *one_args[] = { "one_perl", SAY_HELLO };
char *two_args[] = { "two_perl", SAY_HELLO };
+ PERL_SYS_INIT3(&argc,&argv,&env);
+ one_perl = perl_alloc();
+ two_perl = perl_alloc();
+
PERL_SET_CONTEXT(one_perl);
perl_construct(one_perl);
PERL_SET_CONTEXT(two_perl);
perl_free(one_perl);
PERL_SET_CONTEXT(two_perl);
perl_free(two_perl);
+ PERL_SYS_TERM();
}
Note the calls to PERL_SET_CONTEXT(). These are necessary to initialize
=head1 Hiding Perl_
If you completely hide the short forms forms of the Perl public API,
-add -DPERL_HIDE_SHORT_NAMES to the compilation flags. This means that
+add -DPERL_NO_SHORT_NAMES to the compilation flags. This means that
for example instead of writing
warn("%d bottles of beer on the wall", bottlecount);