From fcc73fe3a6fa113f0a1b2a4ff1f343eaa8661f5b Mon Sep 17 00:00:00 2001 From: Eli Zaretskii Date: Fri, 13 Jan 2006 15:49:03 +0000 Subject: [PATCH] * gdb.texinfo (Sequences): Improve menu annotations. (Define): Add index entries for arguments of user-defined commands. Move the description of flow-control commands... (Command Files): ...to here. Document loop_break and loop_continue. --- gdb/doc/ChangeLog | 8 +++++ gdb/doc/gdb.texinfo | 87 +++++++++++++++++++++++++++++++++++++---------------- 2 files changed, 69 insertions(+), 26 deletions(-) diff --git a/gdb/doc/ChangeLog b/gdb/doc/ChangeLog index 899fe88..e5d8d76 100644 --- a/gdb/doc/ChangeLog +++ b/gdb/doc/ChangeLog @@ -1,3 +1,11 @@ +2006-01-13 Eli Zaretskii + + * gdb.texinfo (Sequences): Improve menu annotations. + (Define): Add index entries for arguments of user-defined + commands. Move the description of flow-control commands... + (Command Files): ...to here. Document loop_break and + loop_continue. + 2006-01-04 Michael Snyder * gdb.texinfo: Add documentation for linux-fork. diff --git a/gdb/doc/gdb.texinfo b/gdb/doc/gdb.texinfo index 5cb3bb0..dd4fd8c 100644 --- a/gdb/doc/gdb.texinfo +++ b/gdb/doc/gdb.texinfo @@ -15974,16 +15974,17 @@ commands for execution as a unit: user-defined commands and command files. @menu -* Define:: User-defined commands -* Hooks:: User-defined command hooks -* Command Files:: Command files -* Output:: Commands for controlled output +* Define:: How to define your own commands +* Hooks:: Hooks for user-defined commands +* Command Files:: How to write scripts of commands to be stored in a file +* Output:: Commands for controlled output @end menu @node Define @section User-defined commands @cindex user-defined command +@cindex arguments, to user-defined commands A @dfn{user-defined command} is a sequence of @value{GDBN} commands to which you assign a new name as a command. This is done with the @code{define} command. User commands may accept up to 10 arguments @@ -16009,6 +16010,8 @@ its three arguments. Note the arguments are text substitutions, so they may reference variables, use complex expressions, or even perform inferior functions calls. +@cindex argument count in user-defined commands +@cindex how many arguments (user-defined commands) In addition, @code{$argc} may be used to find out how many arguments have been passed. This expands to a number in the range 0@dots{}10. @@ -16034,25 +16037,6 @@ The definition of the command is made up of other @value{GDBN} command lines, which are given following the @code{define} command. The end of these commands is marked by a line containing @code{end}. -@kindex if -@kindex else -@item if -@itemx else -Takes a single argument, which is an expression to evaluate. -It is followed by a series of commands that are executed -only if the expression is true (nonzero). -There can then optionally be a line @code{else}, followed -by a series of commands that are only executed if the expression -was false. The end of the list is marked by a line containing @code{end}. - -@kindex while -@item while -The syntax is similar to @code{if}: the command takes a single argument, -which is an expression to evaluate, and must be followed by the commands to -execute, one per line, terminated by an @code{end}. -The commands are executed repeatedly as long as the expression -evaluates to true. - @kindex document @item document @var{commandname} Document the user-defined command @var{commandname}, so that it can be @@ -16085,7 +16069,7 @@ Display the @value{GDBN} commands used to define @var{commandname} (but not its documentation). If no @var{commandname} is given, display the definitions for all user-defined commands. -@cindex infinite recusrion in user-defined commands +@cindex infinite recursion in user-defined commands @kindex show max-user-call-depth @kindex set max-user-call-depth @item show max-user-call-depth @@ -16093,9 +16077,11 @@ definitions for all user-defined commands. The value of @code{max-user-call-depth} controls how many recursion levels are allowed in user-defined commands before GDB suspects an infinite recursion and aborts the command. - @end table +In addition to the above commands, user-defined commands frequently +use control flow commands, described in @ref{Command Files}. + When user-defined commands are executed, the commands of the definition are not printed. An error in any command stops execution of the user-defined command. @@ -16190,6 +16176,7 @@ get a warning from the @code{define} command. @section Command files @cindex command files +@cindex scripting commands A command file for @value{GDBN} is a text file made of lines that are @value{GDBN} commands. Comments (lines starting with @kbd{#}) may also be included. An empty line in a command file does nothing; it @@ -16205,7 +16192,9 @@ command: Execute the command file @var{filename}. @end table -The lines in a command file are executed sequentially. They are not +The lines in a command file are generally executed sequentially, +unless the order of execution is changed by one of the +@emph{flow-control commands} described below. The commands are not printed as they are executed. An error in any command terminates execution of the command file and control is returned to the console. @@ -16228,6 +16217,52 @@ gdb < cmds > log 2>&1 will execute commands from the file @file{cmds}. All output and errors would be directed to @file{log}. +Since commands stored on command files tend to be more general than +commands typed interactively, they frequently need to deal with +complicated situations, such as different or unexpected values of +variables and symbols, changes in how the program being debugged is +built, etc. @value{GDBN} provides a set of flow-control commands to +deal with these complexities. Using these commands, you can write +complex scripts that loop over data structures, execute commands +conditionally, etc. + +@table @code +@kindex if +@kindex else +@item if +@itemx else +This command allows to include in your script conditionally executed +commands. The @code{if} command takes a single argument, which is an +expression to evaluate. It is followed by a series of commands that +are executed only if the expression is true (its value is nonzero). +There can then optionally be an @code{else} line, followed by a series +of commands that are only executed if the expression was false. The +end of the list is marked by a line containing @code{end}. + +@kindex while +@item while +This command allows to write loops. Its syntax is similar to +@code{if}: the command takes a single argument, which is an expression +to evaluate, and must be followed by the commands to execute, one per +line, terminated by an @code{end}. These commands are called the +@dfn{body} of the loop. The commands in the body of @code{while} are +executed repeatedly as long as the expression evaluates to true. + +@kindex loop_break +@item loop_break +This command exits the @code{while} loop in whose body it is included. +Execution of the script continues after that @code{while}s @code{end} +line. + +@kindex loop_continue +@item loop_continue +This command skips the execution of the rest of the body of commands +in the @code{while} loop in whose body it is included. Execution +branches to the beginning of the @code{while} loop, where it evaluates +the controlling expression. +@end table + + @node Output @section Commands for controlled output -- 2.7.4