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ACX_FUNC_FORK
1.1.1.1 (2001/07/26) Miscellaneous @ ac-archive-0.5.39
Mark Elbrecht <snowball3@bigfoot.com>
Check to for a working fork. Use to provide a workaround for systems that don't have a working fork. For example, the workaround for the fork()/exec() sequence for DOS is to use spawn.
Defines HAVE_NO_FORK is fork() doesn't work or isn't implemented.
AC_DEFUN([ACX_FUNC_FORK], [AC_MSG_CHECKING(for a working fork) AC_CACHE_VAL(acx_cv_func_fork_works, [AC_REQUIRE([AC_TYPE_PID_T]) AC_REQUIRE([AC_HEADER_SYS_WAIT]) AC_TRY_RUN([#include <sys/types.h> #ifdef HAVE_SYS_WAIT_H #include <sys/wait.h> #endif #ifdef HAVE_UNISTD_H #include <unistd.h> #endif int main() { int status; pid_t child = fork(); if (child < 0) /* Error */ return (1); else if (child == 0) /* Child */ return (0); /* Parent */ status = (wait(&status) != child); return (status >= 0) ? 0 : 1; } ], acx_cv_func_fork_works=yes, acx_cv_func_fork_works=no, acx_cv_func_fork_works=no) ]) AC_MSG_RESULT($acx_cv_func_fork_works) if test $acx_cv_func_fork_works = no; then AC_DEFINE(HAVE_NO_FORK) fi ])