Implementing new pipe function to get around the limitation

that popen accepts a complete command. We need something which
accepts a program name, and a list of arguments, so that
we don't have to assemble together a correctly quoted string.
popen needs an alternative interface resembling execvp.

* eval.c (eval_init): New intrinsic registered, open-pipe-args.

* stream.c (struct stdio_handle): New member, pid.
(stdio_stream_print): Print the pid, if it is nonzero.
(pipevp_close): New close function.
(pipe_close): If h->pid is nonzero, it's a new-style pipe, which
must be closed with pipev_close.
(make_stdio_stream, make_pipe_stream): Initialize new stdio_handle
member to zero.
(make_pipevp_stream): New static function.
(open_pipevp): New function.

* stream.h (open_pipevp): Declared.

* txr.1: open-pipe-args added to stub section heading.

1 files changed, 1 insertions, 0 deletions

diff --git a/eval.c b/eval.c
index 337f4f80..af8841ac 100644
--- a/eval.c
+++ b/eval.c
@@ -2291,6 +2291,7 @@ void eval_init(void)
   reg_fun(intern(lit("open-directory"), user_package), func_n1(open_directory));
   reg_fun(intern(lit("open-file"), user_package), func_n2(open_file));
   reg_fun(intern(lit("open-pipe"), user_package), func_n2(open_pipe));
+  reg_fun(intern(lit("open-pipe-args"), user_package), func_n3o(open_pipevp, 2));
 
   reg_var(intern(lit("*user-package*"), user_package), &user_package);
   reg_var(intern(lit("*keyword-package*"), user_package), &keyword_package);