[RFA_v2 4/8] Documentation changes for 'frame apply' and 'thread apply'

[Philippe Waroquiers <philippe dot waroquiers at skynet dot be>]

Documents the new commands
   'frame apply'
   faas
   taas
   tfaas

Documents the new arguments FLAGS... added to 'thread apply'

gdb/doc/ChangeLog
2018-05-21  Philippe Waroquiers  <philippe.waroquiers@skynet.be>

	* gdb.texinfo (Debugging Programs with Multiple Threads):
	Document changes to 'thread apply'. Document 'taas'.
	Document 'tfaas'.
	(Examining the Stack): Document 'frame apply'. Document 'faas'.
---
 gdb/doc/gdb.texinfo | 227 +++++++++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 224 insertions(+), 3 deletions(-)

diff --git a/gdb/doc/gdb.texinfo b/gdb/doc/gdb.texinfo
index 4968b374af..4a2bba6139 100644
--- a/gdb/doc/gdb.texinfo
+++ b/gdb/doc/gdb.texinfo
@@ -2936,7 +2936,7 @@ programs:
 @item automatic notification of new threads
 @item @samp{thread @var{thread-id}}, a command to switch among threads
 @item @samp{info threads}, a command to inquire about existing threads
-@item @samp{thread apply [@var{thread-id-list}] [@var{all}] @var{args}},
+@item @samp{thread apply [@var{thread-id-list} | all] @var{args}},
 a command to apply a command to a list of threads
 @item thread-specific breakpoints
 @item @samp{set print thread-events}, which controls printing of 
@@ -3173,7 +3173,7 @@ threads.
 
 @kindex thread apply
 @cindex apply command to several threads
-@item thread apply [@var{thread-id-list} | all [-ascending]] @var{command}
+@item thread apply [@var{thread-id-list} | all [-ascending]] [@var{flags@dots{}}] @var{command}
 The @code{thread apply} command allows you to apply the named
 @var{command} to one or more threads.  Specify the threads that you
 want affected using the thread ID list syntax (@pxref{thread ID
@@ -3182,6 +3182,64 @@ command to all threads in descending order, type @kbd{thread apply all
 @var{command}}.  To apply a command to all threads in ascending order,
 type @kbd{thread apply all -ascending @var{command}}.
 
+The @var{flags} control what output to produce and how to handle
+errors raised when applying @var{command} to a thread.  @var{flags}
+must start with a @code{-} directly followed by one letter in
+@code{vqcs}.  If several flags are provided, they must be given
+individually, such as @code{-c -v -v}.
+
+By default, @value{GDBN} displays some thread information before the
+output produced by @var{command}, and an error raised during the
+execution of a @var{command} will abort @code{thread apply}.  The
+following flags can be used to fine-tune this behavior:
+
+@table @code
+@item -c
+The flag @code{-c}, which stands for @samp{continue}, causes any
+errors in @var{command} to be displayed, and the execution of
+@code{thread apply} then continues.
+@item -s
+The flag @code{-s}, which stands for @samp{silent}, causes any errors
+or empty output produced by a @var{command} to be silently ignored.
+That is, the execution continues, but the thread information and errors
+are not printed.
+@item -v
+The flag @code{-v} (@samp{verbose}) increases the verbosity.
+@item -q
+The flag @code{-q} (@samp{quiet}) decreases the verbosity.
+@end table
+
+Flags @code{-c} and @code{-s} cannot be used together.
+
+The default value of verbosity, 1, prints the per-inferior thread
+number and the target system's thread ID.  Under verbosity 0, no
+thread info is printed.
+
+@kindex taas
+@cindex apply command to all threads (ignoring errors and empty output)
+@item taas @var{command}
+Shortcut for @code{thread apply all -s @var{command}}.
+Applies @var{command} on all threads, ignoring errors and empty output.
+
+@kindex tfaas
+@cindex apply a command to all frames of all threads (ignoring errors and empty output)
+@item tfaas @var{command}
+Shortcut for @code{thread apply all -s frame apply all -s @var{command}}.
+Applies @var{command} on all frames of all threads, ignoring errors
+and empty output.  Note that the flag @code{-s} is specified twice:
+The first @code{-s} ensures that @code{thread apply} only shows the thread
+information of the threads for which @code{frame apply} produces
+some output.  The second @code{-s} is needed to ensure that @code{frame
+apply} shows the frame information of a frame only if the
+@var{command} successfully produced some output.
+
+It can for example be used to print a local variable or a function
+argument without knowing the thread or frame where this variable or argument
+is, using:
+@smallexample
+(@value{GDBP}) tfaas p some_local_var_i_do_not_remember_where_it_is
+@end smallexample
+
 
 @kindex thread name
 @cindex name a thread
@@ -7303,6 +7361,7 @@ currently executing frame and describes it briefly, similar to the
 * Backtrace::                   Backtraces
 * Selection::                   Selecting a frame
 * Frame Info::                  Information on a frame
+* Frame Apply::                 Applying a command to several frames
 * Frame Filter Management::     Managing frame filters
 
 @end menu
@@ -7715,6 +7774,168 @@ accessible at the point of execution of the selected frame.
 
 @end table
 
+@node Frame Apply
+@section Applying a Command to Several Frames.
+@kindex frame apply
+@cindex apply command to several frames
+@table @code
+@item frame apply [all | @var{count} | @var{-count} ] [@var{flags@dots{}}] @var{command}
+The @code{frame apply} command allows you to apply the named
+@var{command} to one or more frames.
+
+@table @code
+@item @code{all}
+Specify @code{all} to apply @var{command} to all frames.
+
+@item @var{count}
+Use @var{count} to apply @var{command} to the innermost @var{count}
+frames, where @var{count} is a positive number.
+
+@item @var{-count}
+Use @var{-count} to apply @var{command} to the outermost @var{count}
+frames, where @var{count} is a positive number.
+@end table
+
+@end table
+
+Note that the frames on which @code{frame apply} applies a command are
+also influenced by the @code{set backtrace} settings such as @code{set
+backtrace past-main} and @code{set backtrace limit N}.  See
+@xref{Backtrace,,Backtraces}.
+
+The @var{flags} control what output to produce and how to handle
+errors raised when applying @var{command} to a frame.  @var{flags}
+must start with a @code{-} directly followed by one letter in
+@code{vqcs}.  If several flags are provided, they must be given
+individually, such as @code{-c -v -v}.
+
+By default, @value{GDBN} displays some frame information before the
+output produced by @var{command}, and an error raised during the
+execution of a @var{command} will abort @code{frame apply}.  The
+following flags can be used to fine-tune this behavior:
+
+@table @code
+@item -c
+The flag @code{-c}, which stands for @samp{continue}, causes any
+errors in @var{command} to be displayed, and the execution of
+@code{frame apply} then continues.
+@item -s
+The flag @code{-s}, which stands for @samp{silent}, causes any errors
+or empty output produced by a @var{command} to be silently ignored.
+That is, the execution continues, but the frame information and errors
+are not printed.
+@item -v
+The flag @code{-v} (@samp{verbose}) increases the verbosity.
+@item -q
+The flag @code{-q} (@samp{quiet}) decreases the verbosity.
+@end table
+
+The following example shows how the flags @code{-c} and @code{-s} are
+working when applying the command @code{p j} to all frames, where
+variable @code{j} can only be successfully printed in the outermost
+@code{#1 main} frame.
+
+@smallexample
+@group
+(gdb) frame apply all p j
+#0  some_function (i=5) at fun.c:4
+No symbol "j" in current context.
+(gdb) frame apply all -c p j
+#0  some_function (i=5) at fun.c:4
+No symbol "j" in current context.
+#1  0x565555fb in main (argc=1, argv=0xffffd2c4) at fun.c:11
+$1 = 5
+(gdb) frame apply all -s p j
+#1  0x565555fb in main (argc=1, argv=0xffffd2c4) at fun.c:11
+$2 = 5
+(gdb)
+@end group
+@end smallexample
+
+The default value of verbosity, 2, prints the location before
+the command output:
+
+@smallexample
+@group
+(gdb) frame apply all p $sp
+#0  some_function (i=5) at fun.c:4
+$4 = (void *) 0xffffd1e0
+#1  0x565555fb in main (argc=1, argv=0xffffd2c4) at fun.c:11
+$5 = (void *) 0xffffd1f0
+(gdb)
+@end group
+@end smallexample
+
+The verbosity 3 prints the location and address:
+
+@smallexample
+@group
+(gdb) frame apply all -v p $sp
+#0  0x565555b1 in some_function (i=5) at fun.c:4
+$6 = (void *) 0xffffd1e0
+#1  0x565555fb in main (argc=1, argv=0xffffd2c4) at fun.c:11
+$7 = (void *) 0xffffd1f0
+(gdb)
+@end group
+@end smallexample
+
+The verbosity 4 prints the source line and address:
+@smallexample
+@group
+(gdb) frame apply all -v -v p $sp
+#0  some_function (i=5) at fun.c:4
+4	   printf ("value of i is %d\n", i);
+$8 = (void *) 0xffffd1e0
+#1  0x565555fb in main (argc=1, argv=0xffffd2c4) at fun.c:11
+11	   some_function (j);
+$9 = (void *) 0xffffd1f0
+(gdb)
+@end group
+@end smallexample
+
+At verbosity 1, only the source line is printed:
+
+@smallexample
+@group
+(gdb) frame apply all -q p $sp
+4	   printf ("value of i is %d\n", i);
+$10 = (void *) 0xffffd1e0
+0x565555fb	11	   some_function (j);
+$11 = (void *) 0xffffd1f0
+(gdb)
+@end group
+@end smallexample
+
+At verbosity 0, no frame information is printed:
+@smallexample
+@group
+(gdb) frame apply all -q -q p $sp
+$12 = (void *) 0xffffd1e0
+$13 = (void *) 0xffffd1f0
+(gdb)
+@end group
+@end smallexample
+
+@table @code
+
+@kindex faas
+@cindex apply a command to all frames (ignoring errors and empty output)
+@item faas @var{command}
+Shortcut for @code{frame apply all -s @var{command}}.
+Applies @var{command} on all frames, ignoring errors and empty output.
+
+It can for example be used to print a local variable or a function
+argument without knowing the frame where this variable or argument
+is, using:
+@smallexample
+(@value{GDBP}) faas p some_local_var_i_do_not_remember_where_it_is
+@end smallexample
+
+Note that the command @code{tfaas @var{command}} applies @var{command}
+on all frames of all threads.  See @xref{Threads,,Threads}.
+@end table
+
+
 @node Frame Filter Management
 @section Management of Frame Filters.
 @cindex managing frame filters
@@ -11093,7 +11314,7 @@ Visiting node of type NODE_INTEGER
 convenience functions.
 
 @table @code
-@item help function
+@item help functionu
 @kindex help function
 @cindex show all convenience functions
 Print a list of all convenience functions.
-- 
2.11.0