X-Git-Url: https://git.exim.org/exim.git/blobdiff_plain/4fc39190bb1254c0117873ab440603136dbb7862..a2204cac393bb160ae7f253b9bb5280fc35ca3a3:/doc/doc-docbook/spec.xfpt?ds=sidebyside

diff --git a/doc/doc-docbook/spec.xfpt b/doc/doc-docbook/spec.xfpt
index 365bd58dd..09ce79848 100644
--- a/doc/doc-docbook/spec.xfpt
+++ b/doc/doc-docbook/spec.xfpt
@@ -9597,11 +9597,25 @@ expansion item above.
         {*&<&'string2'&>&*}}*&"
 .cindex "expansion" "running a command"
 .cindex "&%run%& expansion item"
-The command and its arguments are first expanded separately, and then the
-command is run in a separate process, but under the same uid and gid. As in
-other command executions from Exim, a shell is not used by default. If you want
+.new
+The command and its arguments are first expanded as one string. The string is
+split apart into individual arguments by spaces, and then the command is run
+in a separate process, but under the same uid and gid.  As in other command
+executions from Exim, a shell is not used by default. If the command requires
 a shell, you must explicitly code it.
 
+Since the arguments are split by spaces, when there is a variable expansion
+which has an empty result, it will cause the situation that the argument will
+simply be omitted when the program is actually executed by Exim. If the
+script/program requires a specific number of arguments and the expanded
+variable could possibly result in this empty expansion, the variable must be
+quoted. This is more difficult if the expanded variable itself could result
+in a string containing quotes, because it would interfere with the quotes
+around the command arguments. A possible guard against this is to wrap the
+variable in the &%sg%& operator to change any quote marks to some other
+character.
+.wen
+
 The standard input for the command exists, but is empty. The standard output
 and standard error are set to the same file descriptor.
 .cindex "return code" "from &%run%& expansion"
@@ -12724,8 +12738,9 @@ option), the interfaces and ports on which it listens are controlled by the
 following options:
 
 .ilist
-&%daemon_smtp_ports%& contains a list of default ports. (For backward
-compatibility, this option can also be specified in the singular.)
+&%daemon_smtp_ports%& contains a list of default ports
+or service names.
+(For backward compatibility, this option can also be specified in the singular.)
 .next
 &%local_interfaces%& contains list of interface IP addresses on which to
 listen. Each item may optionally also specify a port.
@@ -12826,7 +12841,8 @@ value of &%daemon_smtp_ports%& is no longer relevant in this example.)
 Exim supports the obsolete SSMTP protocol (also known as SMTPS) that was used
 before the STARTTLS command was standardized for SMTP. Some legacy clients
 still use this protocol. If the &%tls_on_connect_ports%& option is set to a
-list of port numbers, connections to those ports must use SSMTP. The most
+list of port numbers or service names,
+connections to those ports must use SSMTP. The most
 common use of this option is expected to be
 .code
 tls_on_connect_ports = 465