1 files changed, 20 insertions, 1 deletions

diff --git a/doc/pies.texi b/doc/pies.texi
index 012ac88..1a798e1 100644
--- a/doc/pies.texi
+++ b/doc/pies.texi
@@ -176,7 +176,11 @@ foreground.
 
   Upon startup, @command{pies} reads the list of components
 from its configuration file, starts them, and remains in the
-background, controlling their execution.
+background, controlling their execution.  Each component is
+defined by the name of the external program to be run and its
+arguments (command line).  The program is normally run directly
+(via @code{exec}), but you can instruct @command{pies} to run
+it via @code{sh -c} as well.
 
   The standard output and standard error streams of a component can be
 redirected to a file or to an arbitrary @command{syslog} channel.
@@ -870,6 +874,21 @@ their standard input to be open (e.g.@: @command{pppd nodetach}).
 Mark this component as @dfn{precious}.  Precious components are never
 disabled by @command{pies}, even if they respawn too fast.
 
+@kwindex shell
+@item shell
+Run command as @code{/bin/sh -c "$command"}.  Use this flag if command
+contains shell-specific features, such as I/O redirections, pipes,
+variables or the like.  You can change the shell program using the
+@code{program} statement.  For example, to use Korn shell:
+
+@example
+component X @{
+  flags shell;
+  program "/bin/ksh";
+  command "myprog $HOME";
+@}
+@end example
+
 @kwindex wait
 @item wait
 This flag is valid only for @samp{inetd} components.  It has the same