.TH byebug 1
.SH NAME
byebug \- Fast Ruby debugger
.SH SYNOPSIS
.B byebug 
[byebug-options]
byebug
[script-options...]
.SH "DESCRIPTION"
This manual page documents briefly the
.BR byebug
command.
.PP
.B byebug
is a fast implementation of the standard Ruby byebug debug.rb.  It
is implemented by utilizing a Ruby C API hook, allows for remote
debugging and can be used as the Ruby byebug backend interface for a
development environment.
.PP
The commands generally follow gdb's command set unless there's good
reason not to.

.PP
byebug can do four main kinds of things (plus other things in support of
these) to help you catch bugs in the act:

.TP
\ \ \ \(bu
Start or restart your Ruby script, specifying arguments that might
affect its behavior.

.TP
\ \ \ \(bu
Make your program stop at various points possibly determined by
specified conditions.

.TP
\ \ \ \(bu
Examine what has happened when your program has stopped.

.TP
\ \ \ \(bu
Change things in your program, so you can experiment with correcting the
effects of one bug and go on to learn about another.
.PP

Here are some of the most frequently-needed commands:
.TP
.B break \fR[\|\fIfile\fB:\fIline\fR\fR|\fIclass.method\fR] \fR[if \fIexpr\fR]
\&
Set a breakpoint at \c
.I class.method\c
\& or at the specified file and line.
.TP
.B continue \fR[\fIline\fR]
Continue running your program (after stopping, e.g. at a
breakpoint). If a line is given a one-time breakpoint is set there.
.TP
.B delete \fR[\fIbreakpoint-numbers\fR]
\&
Delete breakpoints by number. If no number is given delete all breakpoints.
.TP
.B down \fR[\|\fIcount\fR\|]
Move down one block frame. If count is given move up that many frames. A negative number
goes the other direction and is like the up command
.TP
.B finish
Run until the completion of the current function or method.
.TP
.BI frame " frame-number"
Set the stack frame to \fIframe-number\fR for purposes of examinine local variables. For positioning relative to the current frame, use 
.B up
or 
.B down. A negative number starts counting from the other end.
.TP
.B help \fR[\|\fIname\fR\|]
Show information about byebug command \c
.I name\c
\&, or general information
about using byebug.
.TP
.B info \fR[\|\fIname\fR\|]
Get the various information usually about the debugged program.
.TP
.B irb \fIcommand\fR
Run an interactive ruby shell (irb) using the current environment.
.TP
.B list \fR[\|\fIfile\fB:\fIline\fR|\fIfunction]
type the text of the program in the vicinity of where it is presently stopped
or at the specified function or file and line.
.TP
.B next \fR[\|\fIcount\fR\|]
Execute next program line(s) (after stopping); step \c
.I over\c
\& any
function calls in the line.
.TP
.BI pp " expr"\c
\&
Pretty print the value of an expression.
.TP
.BI print " expr"\c
\&
Display the value of an expression.
.TP
.BI ps " expr"\c
\&
Print an array as a columized sorted list.
.TP
.B quit
Exit byebug.
.TP
.B run \fR[\|\fIarglist\fR\|]
(Re)start your program (with \c
.I arglist\c
\&, if specified). If you want byebug to get reloaded, use
.B restart
instead.
.TP
.B set
Modify parts of byebug's environment.
.TP
.B show
See byebug's environment settings
.TP
.BI source " filename"\c
\&
Read and execute the lines in file \fIfilename\fR as a series of byebug
commands.
.TP
.B step \fR[\|\fIcount\fR\|]
Execute next program line(s) (after stopping); step \c
.I into\c
\& any
function calls in the line.
.TP
.B up \fR[\|\fIcount\fR\|]
Move up one block frame. If count is given move up that many frames. A negative number
goes the other direction and is like the down command
.TP
.B where \fR[\|\fIcount\fR\|]
Display all or \fIcount\fR items of the program stack.
.PP
For full details on byebug, see \c
https://github.com/cldwalker/byebug
.SH OPTIONS
.PP
.TP 10
.TP
.B \-d | \-\-debug
Set $DEBUG true.
.TP
.B \-I | \-\-include PATH
Add PATH to $LOAD_PATH
.TP
.B \-m | \-\-post-mortem
Activate post-mortem mode.
.TP
.B \-\-no\-stop
Do not stop when script is loaded.
.TP
.B \-r | \-\-require SCRIPT
Require the library, before executing your script.
.TP
.B \-\-script FILE
Name of the script file to run.
.TP
.B \-x | \-\-trace
Show lines before executing them.
.TP
.B \-\-no\-quit
Do not quit when script terminates. Instead rerun the program.
.TP
.B \-\-version
Show the version number and exit.
.TP
.B \-\-verbose
Turn on verbose mode.
.TP
.B \-\-v
Print the version number, then turn on verbose mode if a script name
is given. If no script name is given just exit after printing the
version number.
.TP
.B \-\-nx
Don't execute commands found in any initialization files, e.g. .byebugrc.
.TP
.B \-\-keep-frame-binding
Keep frame bindings.
.TP
.B \-\-script=FILE
Name of the script file to run
.TP
.B \-\-help
Show invocation help and exit.
.PD
.SH "SEE ALSO"
.Sp
https://github.com/deivid-rodriguez/byebug
.SH AUTHOR
byebug was written by Kent Siblev. This manual page was written by Rocky
Bernstein <rocky@gnu.org>