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DBX(1-B)                  USER COMMANDS                  DBX(1-B)


NAME
     dbx -- symbolic debugger


SYNOPSIS
     dbx [-r] [-i] [-I dir] [-c command file] objfile [coredump]


DESCRIPTION
     The  dbx command symbolically debugs a user-created program.
     objfile is an object file into  which  symbolic  information
     was  added by specifying a special flag (usually -g) at com-
     pilation.

     Currently, cc(1), CC(1), f77(1), f77sx(1) and f90(1)  create
     symbolic  information.  Additionally, dbx provides a machine
     level debugging function which specifies a program  instruc-
     tion  address or data address. This function does not depend
     on the programming language.

     If a file whose name is 'core' exists in the current  direc-
     tory during dbx execution or argument coredump is specified,
     dbx can check the status in  which  the  program  abnormally
     terminates.

     If  the current directory includes a .dbxinit file, dbx exe-
     cutes a debug command  in  this  file  at  activation.   dbx
     searches  the  current  directory  and the home directory in
     this order for a .dbxinit file.


   Command Line Options
     The command line options and their meanings are as  follows.
     -r        Executes  objfile  immediately.   When the program
               normally terminates,  dbx  terminates.   When  the
               program abnormally terminates, the abnormal termi-
               nation  is  reported  and  the  debug  session  is
               entered.   If  -r  is  specified  and the standard
               input is not a terminal, dbx requests an input  to
               /dev/tty.
     -i        Handles a terminal as the standard input.
     -I dir    Adds  the directory specified in dir to the direc-
               tory list used for source file searching.  In gen-
               eral,   the  current  directory  and  a  directory
               including objfile  are  searched  for  the  source
               file.   The  directory search path can also be set
               by the use command during debugging.
     -c command file
               Reads a debug command from command file  and  exe-
               cutes  it.   If this option is specified, .dbxinit
               is not executed.

   Trace and Execution Commands




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DBX(1-B)                  USER COMMANDS                  DBX(1-B)


     run [args] [< filename] [> filename]
          Start executing objfile. args is passed to  objfile  as
          the  arguments. By using '<' or '>', the standard input
          and output of objfile can be redirected to  a  file  at
          execution. If no argument is specified in run, an argu-
          ment specified in the previous run command is passed.
     trace [in procedure/function] [if condition]
     trace source-line-number [if condition]
     trace procedure/function [in procedure/function] [if condi-
          tion]
     trace expression at source-line-number [if condition]
     trace variable [in procedure/function] [if condition]
          Trace  execution  of objfile and display trace informa-
          tion.  When the trace  command  is  entered,  a  number
          (numeric  value) is given for the command.  This number
          is also used to release the command.  (See  the  delete
          command.)

          The  first  argument specifies the object to be traced.
          If a source-line-number is specified,  source  line  is
          displayed  before  the  source line is executed. If the
          source line number to be specified is  in  the  current
          file,  only  the  line number can be specified.  If the
          source line number to be specified is outside the  cur-
          rent file, the file name is enclosed with double quota-
          tion marks (" ") and the line number linked with  colon
          (:) must be specified (e.g.  "sample.f":17).

          If  a  procedure/function  is  specified for tracing, a
          routine name and a source  line  number  are  displayed
          every time the routine is called.  The parameter values
          are also displayed. Additionally, termination of execu-
          tion  of  the  procedure/function  to be traced is also
          displayed.  The return value of the  function  is  also
          displayed.

          If  the  expression is evaluate, its value is displayed
          whenever it is updated during execution of objfile.  In
          this  specification, execution of objfile is very slow.

          If an  argument  is  specified  in  procedure/function,
          trace information is displayed while the specified pro-
          cedure/function is being executed (including  execution
          of a routine called from it).  If the argument 'if con-
          dition' is specified, the logical expression  condition
          is  evaluated before trace information is displayed. If
          the result is true, trace information is displayed.

     stop if condition
     stop at source-line-number [if condition]
     stop in procedure/function [if condition]
     stop variable [if condition]
          Sets a breakpoint. Stops execution when the given  line
          is reached. When a source-line-number is specified, and



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DBX(1-B)                  USER COMMANDS                  DBX(1-B)


          execution reaches the specified source line,  execution
          of objfile stops. If a procedure/function is specified,
          execution of objfile stops whenever it may  be  called.
          If  a variable is specified, execution of objfile stops
          whenever the contents of the specified variable may  be
          updated.

          If  the argument 'if condition' is specified, the logi-
          cal expression condition is evaluated before  execution
          of  objfile stops.  If the result is true, execution of
          objfile stops.

     status [> filename]
          Displays the content of the command set by the trace or
          stop commands.

     delete command-number ...
     delete all
          Releases  the trace or stop command and invalidates the
          command to which  the  number  is  given.   The  number
          assigned  to  the trace or stop command is displayed by
          the status command.  If all is specified, releases  all
          settings.

     clear [source-line-number]
     clear [procedure/function]
          Releases  all  breakpoints/tracepoints  of source-line-
          number or procedure/function.  When omitting  an  argu-
          ment,  it  releases  all breakpoints and tracepoints at
          the current stopping place.

     catch [signal [signal ...]]
     ignore [signal [signal ...]]
          Sets or releases a trap for a signal sent to a program.
          Execution  of  a program stops before the signal speci-
          fied by the catch command is sent to the program.   The
          ignore command releases the trap. This function enables
          easy debugging of a program which handles a signal such
          as an interrupt. A signal can be specified without pre-
          fix SIG (e.g. SIGINT --> INT).  dbx sets traps for sig-
          nals  except SIGHUP, SIGKILL, SIGALRM, SIGCHLD(SIGCLD),
          SIGTSTP, SIGCONT, SIGKCHKP, SIGKRSTA, SIGTASK and  SIG-
          CORE.

     cont [signal]
     cont [signal] at source-line-number
     cont [signal] in procedure/function
          Restarts execution from the location in which execution
          currently stops. If a signal is specified in the  first
          argument,  the  specified signal is sent to the program
          when execution restarts. A signal name and a number can
          be specified in signal.

          If  'at  source-line-number' or 'in procedure/function'



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          is specified, execution of the program stops when  con-
          trol  passes to the specified source-line-number or the
          specified   procedure/function   call.   This   setting
          restarts execution as the temporary breakpoint.

     step [count]
     next [count]
          Executes  one  line of the source program.  If the cur-
          rent source line is the procedure/function call,  there
          are  differences  between the step command and the next
          command.

          The step command stops execution at  the  beginning  of
          the  procedure/function to be called.  The next command
          executes the called procedure/function.  Then, it stops
          execution at the location to which control passes.

          It executes steps specified by count.

     return [procedure/function]
          Restarts  execution  as  far  as the location where the
          procedure/function specified in  procedure/function  is
          returned. If an argument is omitted, the current proce-
          dure/function is assumed.

     call procedure/function([parameter])
          Executes the procedure/function specified  in  argument
          procedure/function  independently  of  execution of the
          program.  This  function  is  valid   when   a   proce-
          dure/function  is singly tested during program develop-
          ment.


   Display of Variables and Expressions
     dbx searches for the symbol specified in a  command  in  the
     following  order.  First,  dbx  checks whether the symbol is
     included in an active function in the stack.  If the  symbol
     is  not  included  in  the active function, dbx searches all
     files that construct the object program for the  symbol.  If
     the symbol cannot be found using both methods, the following
     message is displayed:

            "symbol" is not defined

     To specify a symbol explicitly without symbol identification
     by dbx, symbol is qualified with the procedure/function or a
     file name (a module name). For example,

            module.function.symbol

     To qualify a symbol with a file name (a module name), a file
     name  whose suffix was deleted (.c in C and .f, .f90 in FOR-
     TRAN) is specified as the module name.




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DBX(1-B)                  USER COMMANDS                  DBX(1-B)


     An expression can be specified in the same syntax as that in
     C. In indirect specification, an asterisk (*) is used at the
     beginning or the hat (^) at the end.  An array subscript  is
     enclosed  with  brackets  ([  ]).  A period (.) is used in a
     field reference. The period can be used for both  the  field
     and  the  pointer.   The C pointer operator (->) can also be
     used.

     The specified expression is checked with its type.  However,
     if  the  type of an expression is specified as the following
     expression, the expression is not checked.

            type-name(expression)

     The representation of &type-name is set as  the  pointer  to
     the specified type.  The representation $$tag-name is set as
     the pointer to the specified the structure tag of C.

     When the contents of array data is referenced, the  contents
     of  all  elements  are displayed unless an element number is
     specified in a symbol.

     The format for specifying element numbers is as follows:

          FORTRAN:  variable [element-number, element-number ...]
          C:        variable [element-number][element-number] ...

     Start-element-number:end-element-number  can  be   specified
     ([0:2],[:3],[3:]).

     To  reference a variable address, an ampersand (&) is speci-
     fied before a symbol. For example,

          (dbx) print &symbol

     In this example, not  the  symbol  content  but  the  symbol
     address is referenced.

     assign variable = expression
     assign register = expression
     assign variable1 => variable2
          Assign  the  value of the expression specified in argu-
          ment expression to the variable specified  in  argument
          variable  or  the register specified in argument regis-
          ter.
          Assign the value of the Fortran90 pointer data or vari-
          able  of  TARGET  attribute specified in argument vari-
          able2 to the Fortran90 pointer data specified in  argu-
          ment variable1.

     dump [procedure/function] [> filename]
     dump . [> filename]
          Displays  names and values of all variables in the pro-
          cedure/function       specified       in       argument



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          procedure/function.

          If  argument procedure/function is omitted, the current
          procedure/function is assumed.

          If  a  period(.)  is  specified   instead   of   proce-
          dure/function, name and values of variables of all pro-
          cedure/function in the stack are displayed.

     print variable [,variable ...]
     print expression [, expression ...]
          Displays the values of the variable  specified  in  the
          argument  variable.  Evaluates the expression specified
          in argument expression and displays the value.

     display [variable [,variable] ...]
     display [expression [,expression] ...]
          Displays the value of the variable specified  in  argu-
          ment  variable whenever execution stops.  Evaluates the
          expression specified in argument expression every  time
          execution  is  stopped  and  displays  the value of the
          result.  When you omit an  argument,  it  displays  the
          list of the currently active variable or expression and
          the display number.

     undisplay variable [,variable] ...
     undisplay expression [,expression] ...
          Stops the display of the value of variable and  expres-
          sion  which was set by the display command.  If expres-
          sion is a constant, undisplay uses the  display  number
          that  is displayed by the display command with no argu-
          ment.

     nullify variable
          To be disassociated Fortran90 pointer data specified in
          argument  variable,  however, data other than Fortran90
          pointer data cannot be specified.

     whatis name
          Displays the type declaration of the variable specified
          in argument name.

     show [arg]
          Displays lists of the symbol names.


          arg  The  argument  that defines the kind of symbols to
               show.  The available argument are as follows:

               vars
                    Local  variables  within  the  current  func-
                    tion(default).





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               globals
                    Global variables.

               commons
                    Names of common blocks that the module refer-
                    nces.

               lines
                    Line numbers in the module.


     which symbol
          Displays the fully qualified name of the symbol  speci-
          fied  in  argument symbol.  This is used when symbol is
          specified  in  the  dbx   command.   Then,   a   proce-
          dure/function  or  a module to which symbol belongs can
          be identified.

     up [count]
     down [count]
          Moves the current  procedure/function  from  the  stack
          level where execution stops.

          The  up  command  is  used  to  move the current proce-
          dure/function toward what calls it by the number speci-
          fied in count.

          The  down  command  is  used to move the current proce-
          dure/function toward what calls it by the number speci-
          fied in count.

          If argument count is omitted, 1 is assumed.

     where [count]
          Displays  the  list  of  the  procedure/function in the
          stack where execution stops. Procedure/function is dis-
          played sequentially from the top of the stack.

     whereis symbol
          Displays  all symbols in the program which are the same
          as the symbol specified in symbol  in  full  qualifica-
          tion.   The  order of the displayed symbol has no mean-
          ing.  It makes it easy to know the fully qualified name
          of  a  symbol  and  the  location  where the symbol was
          defined.


   Accessing a Source File
     /regular expression[/]
     ?regular expression[?]
          Searches the current source file for the pattern speci-
          fied  in  regular expression in the specified direction
          and displays the source line first found. A  slash  (/)
          indicates  a  downward  search, and a question mark (?)



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DBX(1-B)                  USER COMMANDS                  DBX(1-B)


          indicates an upward search.

     edit [filename]
     edit procedure/function
          Invokes an editor by using the file name  specified  in
          filename.  If a procedure/function is specified instead
          of the file name, the editor is invoked  by  using  the
          file including the specified procedure/function.  If an
          argument is omitted, the editor is invoked by using the
          current source file. The editor which is invoked by the
          specified file is vi(1).  To change the editor, specify
          the  desired editor in the environment variable EDITOR.

     file [filename]
          Sets the source file specified in filename to the  cur-
          rent  file. If the argument is omitted, the name of the
          current file is displayed.

     func [procedure/function]
          Sets  the  procedure/function   specified   in   proce-
          dure/function to the current procedure/function.

          If   the   argument  is  omitted,  the  current  proce-
          dure/function is  displayed.   If  the  current  proce-
          dure/function is changed, the source file including the
          changed procedure/function is set to the current  file.

     list [source-line-number [, source-line-number]]
     list source-line-number/[count]
     list procedure/function
          Displays  the source line of the current file.  To dis-
          play from a specific line number  to  a  specific  line
          number,  the  line numbers separated by a comma (,) can
          be specified.  To display two or more lines starting at
          a  specific  line  number,  the  number of lines can be
          specified in /count following the line number at  which
          display  starts. If procedure/function is specified, 10
          lines around the beginning  of  the  procedure/function
          are displayed.

          If  the list command without arguments is specified, 10
          lines are displayed as the default  value  starting  at
          the  line  just  after  the current line. The number of
          lines to be displayed can be changed by setting a value
          to the special debugger variable $listwindow.


     use [directory-list]
          Changes  the  directory  search  pass for a source file
          search to the directory  specified  in  directory-list.
          If  the  argument  is  omitted,  the  current directory
          search pass is displayed.





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DBX(1-B)                  USER COMMANDS                  DBX(1-B)


   Setting Aliases and Variables
     alias name name
     alias name "string"
     alias name (parameters) "string"
          If a command is entered, dbx first checks  whether  the
          input  is a command, or a word defined as an alias of a
          character string. If the word is defined as  an  alias,
          it  is  replaced to the corresponding character string.
          For example,  to  define  "rr"  as  the  alias  of  the
          "return" command, specify as follows:

            alias rr return

          To  define  "b" as the stop command which specifies the
          source line, specify as follows.

            alias b(x) "stop at x"

          As a result, "b (12)" is extended to "stop at 12".

          If the alias command without arguments is entered,  all
          defined alias names are displayed.

     unalias name
          Invalidates  the definition of the alias name specified
          in argument name.

     set name [= expression]
     set  Defines the debugger  variable  specified  in  argument
          name.  A  value  can be specified in the debugger vari-
          able. The debugger variable whose name is the  same  as
          the  variable name in the program being debugged cannot
          be defined.

          If the defined debugger variable is used in another dbx
          command,  it  is  expanded to the corresponding expres-
          sion. If the set command without arguments is  entered,
          the defined debugger variable is displayed.

          The following debugger variables have special meanings.
          (They are called special debugger variables.)

          $frame
               Holds the stack start address of the current  pro-
               cedure/function. It can be referenced by the print
               command. It is set before activating dbx.

          $hexchars
               Displays a character in hexadecimal.

          $hexints
               Displays an integer in hexadecimal.





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DBX(1-B)                  USER COMMANDS                  DBX(1-B)


          $decout
               Displays values of a pointer  and  a  register  in
               decimal.

          $hexoffsets
               Displays  a register offset of machine instruction
               in hexadecimal.

          $hexstrings
               Displays a character string indicated by a charac-
               ter in hexadecimal.

          $advanceoff
               Turns  off the advancing control of CPU.  When the
               advancing control is off, ICC of program  abortion
               is pointed very near to the failed instruction.

          $euc Displays  char,  char  *,  unsigned char, unsigned
               char * as the character or the character string of
               the  EUC  code  set.   $euc  depends on the locale
               environment. The default is defined when  environ-
               ment variable LANG is japan.

          $widechar
               Displays  wchar_t(long/int),  wchar_t *(long */int
               *) as the wide character literal or the wide char-
               acter  string  literal.  In the initial condition,
               it isn't defined.

          $printwide
               Displays many elements of the array in 1  line  as
               much as possible.  It functions only with the FOR-
               TRAN program.

          $int64
               The int64 mode program can be debugged.  Since dbx
               automatically  defines this variable when it  rec-
               ognizes the program, the user doesn't need to per-
               form this function.  If $int64 is defined, dbx can
               handle int/long, the size of  which  is  64  bits.
               dbx  removes  the prefix "_int64_" when displaying
               the symbol and adds the prefix when searching  the
               symbol.

          $prettyprint
               Displays  structure in an indented format with one
               member per line. The default is defined.

          $unionprint
               Displays the contents of  union.  The  default  is
               defined.

          $casesense
               If  $casesense  is  defined,  both  uppercase  and



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               lowercase symbols can be specified.

          $printinput
               Outputs the prompt string and the entered  command
               to stdout.


          The previous debugger variables are set by the set com-
          mand with no parameter specified.


          $unsafecall
          $unsafeassign
               If "$unsafecall" is defined, the type of the argu-
               ment  is  not checked at a procedure/function call
               by the call command.

               If "$unsafeassign" is defined, the  type  of  both
               sides of the assign command are not checked.


          These  variables  place restrictions on error detection
          of the dbx command.


          $listwindow
               A value set to this variable is used as the number
               of lines to be displayed by the list command with-
               out arguments. The default value for the number of
               lines to be displayed is 10.

          $floatmode
               Indicate the floating-point data format handled by
               dbx (SX-4 only).

               0    :The floating-point data is float0 format.
               1    :The floating-point data is float1 format.
               2    :The floating-point data is float2 format.

               dbx determines the floating-point data  format  at
               in  the  following sequence at its activation, and
               set a value automatically in $floatmode.
               In general, if it can not determines the floating-
               point  data format by compiling an object program,
               determines the format by referencing the  environ-
               ment  value  FLMOD.   If it can not determines the
               format by referencing FLMOD,  assumes  the  float0
               format.

          $maxstrlen
               Sets  maximum  displaying  string length in C. The
               default value is 1024.





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DBX(1-B)                  USER COMMANDS                  DBX(1-B)


          $lines
               The value of this variable is used to set the num-
               ber  of  lines  on  a  screen.  When the number of
               lines displayed by a command are over the value of
               $lines,  dbx  asks  user, whether to continue dis-
               playing or not.  If $lines is not set,  or  $lines
               is  set  to  a value of 2 or less, dbx ignores the
               $lines variable.  The default value  is  the  con-
               tents  of  the  environment  variable LINES.  When
               LINES is not set, the value of $lines is set  from
               terminfo.   If  the  value is not set in terminfo,
               then $lines is set to 23.  This value  is  updated
               automatically  when  the window size is changed on
               the terminal emulator, such as Xterm.

          $columns
               The value of this variable is used to set the num-
               ber  of  columns  on a screen.  If $columns is not
               set, or $columns is set to a value of 0  or  less,
               dbx  assumes that 1 line to the starting new line.
               The default value is the contents of the  environ-
               ment  variable  COLUMNS.  When COLUMNS is not set,
               the value of $columns is set  from  terminfo.   If
               the value is not set in terminfo, then $columns is
               not set.  This value is updated automatically when
               the  window size is changed on the terminal emula-
               tor, such as Xterm.

          $dim1 - $dim7
               The values of these variables mean maximum  number
               of  elements in arrays which are displayed.  $dim1
               is first dimension, $dim2 is second, and so on. It
               is possible to specify till seventh dimension.  If
               the value is not set or the value is set except  1
               to  16777216,  then  dbx  does not limit to display
               them.



     unset name
          Invalidates the definition  of  the  debugger  variable
          specified in argument name.


   Machine Level Debugging Commands
     tracei [address] [if condition]
     tracei [variable [at address]] [if condition]
     stopi if condition
     stopi at address [if condition]
     stopi address [if condition]
          The  functions of the tracei and stopi commands are the
          same as those of the trace and stop commands. The loca-
          tion  where  execution  is  to  be traced or stopped is
          specified with addresses.



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DBX(1-B)                  USER COMMANDS                  DBX(1-B)


     stepi [count]
     nexti [count]
          The functions of the stepi and nexti commands  are  the
          same  as those of the step and next commands. A program
          is executed not by the source step but by the  instruc-
          tion.  It executes instructions specified by count.

     cleari [address]
          Releases  all breakpoints/tracepoints of address.  When
          you omit an argument, it releases all  breakpoints  and
          tracepoints at the current stopping place.

     address1,address2/[mode]
     address/[count] [mode]
          Displays  the contents of the specified memory. To ref-
          erence the contents  of  the  memory  between  specific
          addresses, address1 which starts reference and address2
          which ends reference can  be  specified  by  separating
          with  a comma (,).  The display format can be specified
          in mode. If the display format is omitted, the specifi-
          cation  of the previous input mode is assumed. The ini-
          tial display format of mode set by dbx is X.

          Additionally, the contents of the memory can be  refer-
          enced  by the number specified in count from a specific
          address in the display format specified in mode.

          The following mode types are supported for the  display
          format.

          i    Displays in the disassembled format
          d    Displays in decimal by the 2-byte unit
          D    Displays in decimal by the 4-byte unit
          DD   Displays in decimal by the 8-byte unit
          o    Displays in octal by the 2-byte unit
          O    Displays in octal by the 4-byte unit
          OO   Displays in octal by the 8-byte unit
          x    Displays in hexadecimal by the 2-byte unit
          X    Displays in hexadecimal by the 4-byte unit
          XX   Displays in hexadecimal by the 8-byte unit
          b    Displays in octal by the byte
          c    Displays in character by the byte
          s    Displays in the character string format which ends
               with a null byte
          f    Displays in the floating-point constant format
          g    Displays in  the  double-precision  floating-point
               constant format
          q    Displays in the quadruple-precision floating-point
               constant format

          An address can be specified by an expression. The oper-
          ators to be used are +, -, and indirect *.





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DBX(1-B)                  USER COMMANDS                  DBX(1-B)


   Specifying a Register
     A  register  is specified with a register name preceded by a
     dollar mark ($) (e.g. $s1, $s2 ...). A register can be spec-
     ified  instead  of  a variable name. Register specifications
     are as follows.
          $icc, $pc           Instruction counter
          $ice                Interrupt caused icc
          $sN (N:0...127)     Scalar register
          $vN (N:0...7)       Vector arithmetic register
          $vdN (N:0...255)    Vector data register
          $vc                 Vector control register
          $vmN (N:0...15)     Vector mask register
          $vl                 Vector length register
          $psw                Process status word
          $ipr                Interrupt cause
          $ex                 Execution counter

     The following registers are defined as registers  with  spe-
     cial meanings.
          $slp      Register holding the stack limit pointer
          $sfp      Register holding the stack frame pointer
          $sp       Register holding the stack pointer
          $ap       Register  holding  the  pointer  to the argu-
                    ment/parameter list
          $lcp      Register holding the linkage section pointer


     The method of the range specification is as follows.
          $register-name[m:l]
                    m and l are decimal integers (m<l).  A  vari-
                    able  can also be specified.  m indicates the
                    location where display starts,  and  l  indi-
                    cates the location where display ends.

     The range specification is possible for the following regis-
     ters.
          $vN[m:l]  Vector arithmetic  register.   The  range  is
                    from 0 to 255.
          $vdN[m:l] Vector data register.  The range is from 0 to
                    255.
          $vc[m:l]  Vector control register.  The range is from 0
                    to 3.
          $vmN[m:l] Vector mask register.  The range is from 0 to
                    3.

     If m or l is omitted, the range specification is as follows.
          $vN[m:]   from m to the end
          $vN[:l]   from the beginning to l
          $vN[m]    only m
          $vN       from the beginning to the end






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DBX(1-B)                  USER COMMANDS                  DBX(1-B)

   Other Commands
     help [item]
          Displays the summary of the dbx command. If the item is
          specified, the detail information  on  the  command  is
          displayed.

     quit Terminates  dbx. The process during debugging also ter-
          minates.


     sh [command-line]
          Sends the command entered in argument  command-line  to
          the shell and executes it. The shell to be activated is
          set to the SHELL environment variable.  If the sh  com-
          mand  is specified without arguments, the shell remains
          activated.

     source filename
          Reads the dbx command described in file filename  which
          is specified in the argument and executes it.


NOTES
   [The Floating-point data Format]
     dbx  for  SX-4 can handle float0, float1 and float2 floating-
     point data format.  In general, if a special option  is  not
     specified  at  compilation,  an  object program is generated
     which handle a floating-point  data  format  determined  for
     each  system.  Since dbx automatically identifies the float-
     ing-point data format from object file, a user need not con-
     sider it.

     If  a  object  file is mixed, (the each of source files were
     compiled by float0 mode, float1 mode  or  float2  mode,  and
     linked  by  ld(1))  dbx  handles the object program in the
     default floating-point data format defined  in  the  system.
     If  it  does not suit, set a value to special debugger vari-
     able $floatmode.


   [core file]
     In the SUPER-UX R7.1 or later, the core file name  has  changed
     from 'core' (in the SUPER-UX R6.2 or earlier) to 'core.process-
     ID'.  If you want to analyze the core file, you must specify
     a core file name explicitly on the command line.


FILES
      a.out              an object file
      .dbxinit           an initial command file
      core               a core dump file

NOTICE
     - Please  specify  the -C debug option when compiling a pro-
       gram with the f77(1) command.
       f77(1) command treats the option -C debug as -Wf,"-NO  -Nv
       -Ni -d -g -stmtid".



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DBX(1-B)                  USER COMMANDS                  DBX(1-B)


     - The  following  warnings  apply to debug programs compiled
       with the f77(1) command or the f77sx(1) command with  fopp
       preprocessor.

       (1) The source file that dbx accesses with list or other
         commands is not the source file specified at compilation
         but the source file with a  "v."  prefix.   In  case  of
         f77(1)  command specify -EO, f77sx(1) command speify -Nt
         -fopp, cc(1) command specify -P.

       (2) The file with a "v." prefix includes the source file
         modified by the fopp preprocessor, and the  line  number
         displayed  by  dbx is the line number of the file with a
         "v." prefix.  The line number used with stop at  command
         is  also that of the file with a "v." prefix.  Line num-
         bers of the original source file  are  showed  after  73
         columns of each line in the file with a "v." prefix.

     - The  f77sx(1)  command  does not automatically degrade the
       optimization level even if option -g is specified.   Thus,
       no executable statement is generated at the insertion to a
       variable not referenced in the program, and  a  breakpoint
       may  be set to the next line.  To degrade the optimization
       level with f77sx(1), specify option -NO.

     - If a program exception occurs, icc indicates  the  address
       preceding  by  several  instructions beyond the address at
       which the exception occurs, since this uses advancing con-
       trol  of  the  CPU. Thus, the source line displayed by dbx
       may not be the same as the  one  at  which  the  exception
       occurs.   CPU  advancing control is suppressed when a pro-
       gram  is  executed  by  setting  the   debugger   variable
       $advanceoff.   In   this  case,  if  a  program  exception
       occurred, the value of icc points to the  address  of  the
       command  following the command which caused the exception,
       thus the correct source line is displayed.  Note, however,
       that program execution speed decreases when $advanceoff is
       set.

     - SUPER-UX provides the following two types of dbx.

       (1) dbx executing in the 1MB paging mode(dbx.1m).
         This type of dbx allows use of large memory  for  debug-
         ging  a  large-scale program.  dbx.1m is linked(ln) with
         dbx as default at release.

       (2) dbx executing in the 32KB paging mode(dbx.32k)
         This type of dbx does not allow the use of large memory,
         but its response speed is relatively high.

       dbx.1m is advantageous for debugging a source program hav-
       ing up to 4000 lines.
       When an alias of csh(1) is used as shown below, which  dbx
       should  be  used  is  clarified to make good use of either
       dbx.1m or dbx.32k.

            % alias dbx.small dbx.32k
            % alias dbx.large dbx.1m

       dbx is installed  in  the  directory  /usr/bin,  and  this
       directory must be set in the environment variable PATH.



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DBX(1-B)                  USER COMMANDS                  DBX(1-B)


SEE ALSO
     cc(1) 
     CC(1) in SUPER-UX C++ Language Reference Manual
     f77(1), f77sx(1) in SUPER-UX FORTRAN77/SX Language Reference Manual
     f90(1) in SUPER-UX FORTRAN90/SX Language Reference Manual
























































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G1AB02E Programmer's Reference Manual