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2008-02-29 Joel Sherrill <joel.sherrill@oarcorp.com>

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* shell/general.t: Add sleep and echo commands.
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Joel Sherrill
2008-02-29 23:20:29 +00:00
parent c2153cfd29
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doc/ChangeLog
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@@ -1,3 +1,7 @@
2008-02-29 Joel Sherrill <joel.sherrill@oarcorp.com>
* shell/general.t: Add sleep and echo commands.
2008-02-28 Joel Sherrill <joel.sherrill@oarcorp.com>
* shell/.cvsignore, shell/Makefile.am, shell/memory.t,

208
doc/shell/general.t
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@@ -16,6 +16,8 @@ The RTEMS shell has the following general commands:
@item @code{alias} - Add alias for an existing command
@item @code{date} - Print or set current date and time
@item @code{echo} - Produce message in a shell script
@item @code{sleep} - Delay for a specified amount of time
@item @code{id} - show uid gid euid and egid
@item @code{tty} - show ttyname
@item @code{whoami} - print effective user id
@@ -186,6 +188,212 @@ following prototype:
extern rtems_shell_cmd_t rtems_shell_DATE_Command;
@end example
@c
@c
@c
@page
@subsection echo - produce message in a shell script
@pgindex echo
@subheading SYNOPSYS:
@example
echo [-n | -e] args ...
@end example
@subheading DESCRIPTION:
echo prints its arguments on the standard output, separated by spaces.
Unless the @b{-n} option is present, a newline is output following the
arguments. The @b{-e} option causes echo to treat the escape sequences
specially, as described in the following paragraph. The @b{-e} option is the
default, and is provided solely for compatibility with other systems.
Only one of the options @b{-n} and @b{-e} may be given.
If any of the following sequences of characters is encountered during
output, the sequence is not output. Instead, the specified action is
performed:
@table @b
@item \b
A backspace character is output.
@item \c
Subsequent output is suppressed. This is normally used at the
end of the last argument to suppress the trailing newline that
echo would otherwise output.
@item \f
Output a form feed.
@item \n
Output a newline character.
@item \r
Output a carriage return.
@item \t
Output a (horizontal) tab character.
@item \v
Output a vertical tab.
@item \0digits
Output the character whose value is given by zero to three digits.
If there are zero digits, a nul character is output.
@item \\
Output a backslash.
@end table
@subheading EXIT STATUS:
This command returns 0 on success and non-zero if an error is encountered.
@subheading NOTES:
The octal character escape mechanism (\0digits) differs from the C lan-
guage mechanism.
There is no way to force @code{echo} to treat its arguments literally, rather
than interpreting them as options and escape sequences.
@subheading EXAMPLES:
The following is an example of how to use @code{echo}:
@example
SHLL [/] $ echo a b c
a b c
SHLL [/] $ echo
@end example
@subheading CONFIGURATION:
@findex CONFIGURE_SHELL_NO_COMMAND_ECHO
@findex CONFIGURE_SHELL_COMMAND_ECHO
This command is included in the default shell command set.
When building a custom command set, define
@code{CONFIGURE_SHELL_COMMAND_ECHO} to have this
command included.
This command can be excluded from the shell command set by
defining @code{CONFIGURE_SHELL_NO_COMMAND_ECHO} when all
shell commands have been configured.
@subheading PROGRAMMING INFORMATION:
@findex rtems_shell_rtems_main_echo
The @code{echo} is implemented by a C language function
which has the following prototype:
@example
int rtems_shell_rtems_main_echo(
int argc,
char **argv
);
@end example
The configuration structure for the @code{echo} has the
following prototype:
@example
extern rtems_shell_cmd_t rtems_shell_ECHO_Command;
@end example
@subheading ORIGIN:
The implementation and portions of the documentation for this
command are from NetBSD 4.0.
@c
@c
@c
@page
@subsection sleep - delay for a specified amount of time
@pgindex sleep
@subheading SYNOPSYS:
@example
sleep seconds
sleep seconds nanoseconds
@end example
@subheading DESCRIPTION:
This command causes the task executing the shell to block
for the specified number of @code{seconds} and @code{nanoseconds}.
@subheading EXIT STATUS:
This command returns 0 on success and non-zero if an error is encountered.
@subheading NOTES:
This command is implemented using the @code{nanosleep()} method.
The command line interface is similar to the @code{sleep} command
found on POSIX systems but the addition of the @code{nanoseconds}
parameter allows fine grained delays in shell scripts without
adding another command such as @code{usleep}.
@subheading EXAMPLES:
The following is an example of how to use @code{sleep}:
@example
SHLL [/] $ sleep 10
SHLL [/] $ sleep 0 5000000
@end example
It is not clear from the above but there is a ten second
pause after executing the first command before the prompt
is printed. The second command completes very quickly
from a human perspective and there is no noticeable
delay in the prompt being printed.
@subheading CONFIGURATION:
@findex CONFIGURE_SHELL_NO_COMMAND_SLEEP
@findex CONFIGURE_SHELL_COMMAND_SLEEP
This command is included in the default shell command set.
When building a custom command set, define
@code{CONFIGURE_SHELL_COMMAND_SLEEP} to have this
command included.
This command can be excluded from the shell command set by
defining @code{CONFIGURE_SHELL_NO_COMMAND_SLEEP} when all
shell commands have been configured.
@subheading PROGRAMMING INFORMATION:
@findex rtems_shell_rtems_main_sleep
The @code{sleep} is implemented by a C language function
which has the following prototype:
@example
int rtems_shell_rtems_main_sleep(
int argc,
char **argv
);
@end example
The configuration structure for the @code{sleep} has the
following prototype:
@example
extern rtems_shell_cmd_t rtems_shell_SLEEP_Command;
@end example
@c
@c
@c