From 92ce7cf665cc0b51e515c2f3fa4e3715c9cc9e24 Mon Sep 17 00:00:00 2001 From: Markus Armbruster Date: Sun, 5 Apr 2009 10:55:46 +0200 Subject: [PATCH] Belatedly document batch file restrictions The server rejects redirections in batch files since commit ed8e0cd5, and execute commands since commit adfab434, both v4.3.11. --- doc/clients-howto | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) diff --git a/doc/clients-howto b/doc/clients-howto index 2a986e376..4ddad66ac 100644 --- a/doc/clients-howto +++ b/doc/clients-howto @@ -242,12 +242,14 @@ The following ids occur: signal interrupt if it is unable or unwilling to send the complete batch file. - While executing the batch file, the server sends no C_PROMPT command - prompts. It still sends C_FLUSH argument prompts. + While executing the batch file, the server rejects redirections and + execute commands, and sends no C_PROMPT command prompts. It still + sends C_FLUSH argument prompts. Protocol flaw: not sending C_PROMPT here screws up redirections: - they apply until the next C_PROMPT, i.e. from start of redirected - command until end of containing batch file. + they'd apply until the next C_PROMPT, i.e. from start of redirected + command until end of containing batch file. That's why the server + rejects redirections in batch files. Certain bad failures make the server ignore the rest of the batch file file. This feature is too hard to predict to be really useful. @@ -255,7 +257,10 @@ The following ids occur: Protocol flaw: strictly asynchronous clients cannot support C_EXECUTE correctly. By the time C_EXECUTE arrives, the client may have sent more input already. That input `overtakes' the contents - of the batch file in the input stream. + of the batch file in the input stream, and is interpreted as part of + the batch file. Because this is almost certain to happen when the + execute comes from a batch file, the server rejects execute commands + there. emp_client has this problem. -- 2.43.0