unixsys: check for system() in configure

Don't let a non-available system() function (happens e.g. on iOS)
prevent us from compiling ECL.

msvc/ecl/config-internal.h.msvc6

@@ -113,19 +113,7 @@
 /* #undef HAVE_SYS_WAIT_H */
 /* size of long long            					*/
 #define ECL_LONG_LONG_BITS 64
-
-/*
- * we do not manage to get proper signal handling of floating point
- * arithmetics in the Alpha chips.
- */
-#if defined(__alpha__)
-# ifdef HAVE_FENV_H
-#  undef HAVE_FENV_H
-# endif
-# ifdef HAVE_FEENABLEEXCEPT
-#  undef HAVE_FEENABLEEXCEPT
-# endif
-#endif
+#define HAVE_SYSTEM
 
 /* what characters are used to mark beginning of new line		*/
 #define ECL_NEWLINE_IS_CRLF 1

src/c/unixsys.d

@@ -39,9 +39,14 @@
 cl_object
 si_system(cl_object cmd_string)
 {
-	cl_object cmd = si_copy_to_simple_base_string(cmd_string);
-	int code = system((const char *)(cmd->base_string.self));
-	return ecl_make_fixnum(code);
+#if !defined(HAVE_SYSTEM)
+  FElibc_error("si_system not implemented",1);
+  @(return ECL_NIL);
+#else
+  cl_object cmd = si_copy_to_simple_base_string(cmd_string);
+  int code = system((const char *)(cmd->base_string.self));
+  @(return ecl_make_fixnum(code));
+#endif
 }
 
 cl_object

src/configure

@@ -9444,7 +9444,7 @@ done
 
 for ac_func in nanosleep alarm times select setenv putenv \
                 lstat mkstemp sigprocmask isatty tzset \
-		gettimeofday getrusage
+                gettimeofday getrusage system
 do :
   as_ac_var=`$as_echo "ac_cv_func_$ac_func" | $as_tr_sh`
 ac_fn_c_check_func "$LINENO" "$ac_func" "$as_ac_var"
@@ -9469,7 +9469,7 @@ fi
 
 
 for ac_func in expf powf logf sqrtf cosf sinf tanf sinhf coshf tanhf \
-		floorf ceilf fabsf frexpf ldexpf log1p log1pf log1pl \
+                floorf ceilf fabsf frexpf ldexpf log1p log1pf log1pl \
                 copysign
 do :
   as_ac_var=`$as_echo "ac_cv_func_$ac_func" | $as_tr_sh`

src/configure.ac

@@ -737,14 +737,14 @@ dnl !!! end autoscan
 
 AC_CHECK_FUNCS( [nanosleep alarm times select setenv putenv] \
                 [lstat mkstemp sigprocmask isatty tzset] \
-		[gettimeofday getrusage] )
+                [gettimeofday getrusage system] )
 AC_CHECK_DECL([feenableexcept],
               [AC_DEFINE(HAVE_FEENABLEEXCEPT,[],[feenableexcept is available])],
               [AC_MSG_WARN(feenableexcept not declared: disabling floating point exceptions)],
               [#include <fenv.h>])
 
 AC_CHECK_FUNCS( [expf powf logf sqrtf cosf sinf tanf sinhf coshf tanhf] \
-		[floorf ceilf fabsf frexpf ldexpf log1p log1pf log1pl] \
+                [floorf ceilf fabsf frexpf ldexpf log1p log1pf log1pl] \
                 [copysign] )
 
 AC_CHECK_FUNCS( [sched_yield uname fseeko dladdr backtrace backtrace_symbols] )

src/ecl/configpre.h

@@ -519,6 +519,9 @@
 /* Define to 1 if you have the `strtol' function. */
 #undef HAVE_STRTOL
 
+/* Define to 1 if you have the `system' function. */
+#undef HAVE_SYSTEM
+
 /* Define to 1 if you have the <sys/dir.h> header file, and it defines `DIR'.
    */
 #undef HAVE_SYS_DIR_H

src/h/config-internal.h.in

@@ -149,6 +149,7 @@
 #undef HAVE_BACKTRACE
 #undef HAVE_BACKTRACE_SYMBOLS
 #undef HAVE_SCHED_H
+#undef HAVE_SYSTEM
 
 /* what characters are used to mark beginning of new line               */
 #undef ECL_NEWLINE_IS_CRLF