| SET THREAD | ||
| Syntax | Hc<n> | Set step/continue thread (-1 == all threads). |
| Hg<n> | Set general operation thread (0 == any thread). | |
| Reply | OK, E<n> | n == two-digit error code. |
| READ REGISTERS | ||
| Syntax | g | Get all cpu registers. |
| Reply | hex-data | Data consists of a single block of hex data representing the concatenation of the values of all registers. GDB must know their order and size to pick the values apart. Data is in target byte order. |
| E<n> | n == two-digit error code. | |
| WRITE REGISTERS | ||
| Syntax | G<hex-data> | Set all cpu registers. Data consists of a single block of hex data representing the concatenation of the values of all registers. Stub must know their order and size to pick the values apart. Data is in target byte order. |
| Reply | OK, E<n> | n == two-digit error code. |
| WRITE SINGLE REGISTER | ||
| Syntax: | P<n>=<value> | Set value of selected register. n == register number, value == new value in hex (target byte order). |
| Reply | OK, E<n> | n == two-digit error code. |
| "" | WRITE SINGLE REGISTER not supported by this stub. | |
| READ MEMORY | ||
| Syntax | m<addr>,<len> | Read len bytes starting at memory address addr. |
| Reply | hex-data | The values of the requested memory in target byte order. May be shorter than requested, if some of the memory could not be read. |
| E<n> | n == two-digit error code. | |
| NOTE: partial success should be reported as an error. | ||
| WRITE MEMORY | ||
| Syntax | M<addr>,<len>:<hex-data> | Write len bytes starting at memory address addr, with the values of the following data block (which is in target byte order). |
| Reply | OK, E<n> | n == two-digit error code. |
| NOTE: partial success should be reported as an error. | ||
| CONTINUE | ||
| Syntax | c, or c<addr> | Continue the target program (starting from addr if present, else from last known program counter). |
| Reply | No reply is sent until the target stops; then the reply is the same as for GET REASON FOR STOPPING. | |
| CONTINUE WITH SIGNAL | ||
| Syntax | C<signal>, or C<signal>;<addr> | Continue the target program (starting from addr if present, else from last known program counter), but cause it to behave as if receiving signal "signal". |
| Reply | No reply is sent until the target stops; then the reply is the same as for GET REASON FOR STOPPING. | |
| SINGLE-STEP | ||
| Syntax | s, or s<addr> | Single-step the target program (starting from addr if present, else from last known program counter). |
| Reply | No reply is sent until the target stops; then the reply is the same as for GET REASON FOR STOPPING. | |
| SINGLE-STEP WITH SIGNAL | ||
| Syntax | S<signal>, or S<signal>;<addr> | Single-step the target program (starting from addr if present, else from last known program counter), but cause it to behave as if receiving signal "signal". |
| Reply | No reply is sent until the target stops; then the reply is the same as for GET REASON FOR STOPPING. | |
| GET REASON FOR STOPPING | ||
| Syntax | ? | Get the (unix-like) signal number representing the reason for the most recent target stop (usually an exception or trap). |
| Reply | S<signal> | Target stopped with (unix-like) signal "signal". |
| T<signal>[<regnum>:<value>]+ | Target stopped with (unix-like) signal "signal", and with the following list of register values in arbitrary order. As always, register values (if present) are in target byte order. Note that the "T" reply is an enhancement not implemented by all stubs. | |
| W<exitcode> | Target process exited with exitcode. Not supported by all stubs. | |
| X<signal> | Target process terminated with signal "signal". Not supported by all stubs. | |
| IS THREAD ALIVE | ||
| Syntax | T<threadnum> | Find out if thread threadnum is alive. |
| Reply | OK, E<n> | n is ignored; simply means thread is not alive. |
| REMOTE RESTART | ||
| Syntax | R<value> | Restart the remote server. |
| Reply | No reply will be sent. This message is normally followed by GET REASON FOR STOPPING. | |
| REMOTE KILL | ||
| Syntax | k | Kill the remote process. |
| Reply | "" | Some stubs may reply with an empty packet; however GDB does not wait for a reply. |
| REMOTE DETACH | ||
| Syntax | D | Detach the remote process from the server/stub. For most stubs, this is a no-op. |
| Reply | "" | GDB does not wait for a reply. |
| SET BAUDRATE | ||
| Syntax | b<n> | n is the desired baudrate, in hex. |
| Reply | OK | Baud rate was set to n. |
| B01 | Not supported. | |
| TOGGLE DEBUG | ||
| Syntax | d | Toggle the stub debug mode (on to off, or off to on). |
| Reply | "" | This message is never used by GDB. |
| REMOTE RESET | ||
| Syntax | r | Reset the remote target board. |
| Reply | Target will not reply, but will immediately reset. | |
| USE EXTENDED SYNTAX | ||
| Syntax | ! | Use "extended remote protocol" extensions. This message is "sticky"; it only needs to be sent once. |
| Reply | "" | Reply is ignored by GDB. |
| GENERAL QUERY | ||
| Syntax | q<anything> | A general purpose command for extending the protocol, or defining target-specific queries. |
| Reply | <anything> | Replies will be defined for the specific query messages. |
| GENERAL SET | ||
| Syntax | Q<anything> | A general purpose command for extending the protocol, or defining target-specific "set" requests. |
| Reply | <anything> | Replies will be defined for the specific set messages. |
| UNKNOWN MESSAGE | ||
| Syntax | Anything not covered above. | All stubs should ignore any message that is correctly formatted (with checksum), yet otherwise unknown to them. |
| Reply | "" | The correct reply for an unrecognized message is an empty packet. |
| VERBOSE REPLY | ||
| Syntax | O<hex-data> | In certain circumstances (notably when the target process is running, ie. between receipt of CONTINUE/STEP and the reply of GET REASON FOR STOPPING), the stub may send a verbose message to GDB. This reply contains an arbitrary ascii string, encoded as two hex bytes per ascii character. GDB is expected to display this string to the console. |
| QUERY TRACE STATUS | ||
| Syntax | qTStatus | Get the status of the target trace subsystem. |
| Reply | T0 | Trace not running. |
| T1 | Trace is running. | |
| "" | Empty packet: target does not support tracing. | |
| INITIALIZE TRACE SUBSYSTEM | ||
| Syntax | QTinit | Set trace subsystem to "initialized" state (whatever that entails). |
| Reply | OK | Target trace initialized. |
| "" | Empty packet: target does not support tracing. | |
| START TRACE | ||
| Syntax | QTStart | Set trace subsystem to "running" state (insert trace traps etc., begin collecting data). |
| Reply | OK | Target trace started, trace traps inserted. |
| "" | Empty packet: target does not support tracing. | |
| STOP TRACE | ||
| Syntax | QTStop | Set trace subsystem to "not running" state (remove trace traps etc., cease collecting data). |
| Reply | OK | Target trace stopped, trace traps removed. |
| "" | Empty packet: target does not support tracing. | |
| SET TRACEPOINT | ||
| Syntax | QTDP:[-]<id>:<addr>:<attributes>[-] | Set (define) a tracepoint with id, address and other attributes as follows. If the message ends in a dash (-), then it is to be continued in the next message. If the id is preceeded by a dash (-), then this message is a continuation of the preceeding one. |
| Syntax of attributes: | <enabled>: | Values are 'E' (enabled) or 'D' (disabled). Required and position-dependent, can only cocur in the first message of a split SET TRACEPOINT request, following <addr>: |
| <stepcount>: | How many times to single-step after tracepoint trap. Required and position dependent, can only occur in the first message of a split SET TRACEPOINT request, following <enabled>: | |
| <passcount>: | Number of times to allow this tracepoint to be triggered before automatically invoking STOP TRACE. Required and position dependent, can only occur in the first message of a split SET TRACEPOINT request, following <stepcount>: | |
| R<register-mask> | Each 'on' bit in the register mask represents a register to be collected at the trace event. With the rightmost bit representing register zero, the registers are numbered in the same order that GDB and the stub already agree upon for all other register operations. | |
| M<regnum>,<offset>,<len> | Memory range to be collected at the trace event. Each tracepoint definition may have an arbitrary number of memrange attributes. Regnum, offset and len are hex numbers. A positive integer regnum represents a memory range with a register-relative starting offset; otherwise the starting offset is absolute. | |
| X<len>,<bytecode> | Bytecode string to be executed at the trace event. Len represents the length of the bytecode string. Each tracepoint definition may have an arbitrary number of bytecode attributes. The format of the bytecode string is described in The GDB Agent Expression Mechanism. | |
| S | Fencepost token, separating the preceeding R, M and X attributes (to be collected at the trace trap event) from the following R, M and X attributes (to be collectted while single-stepping). Optional, and there can be only one per tracepoint definition. If this token is not present, then all R, M and X attributes apply to the trace trap event (not to stepping events). | |
| Reply | OK | Tracepoint definition accepted. |
| E<n> | Tracepoint definition rejected (error codes TBD). | |
| "" | Target does not support tracepoints. [NOTE: this may not mean that the target does not support tracing. Some targets may support some extremely simple form of tracing which might, for instance, simply be "on" or "off".] | |
| REQUEST TRACE FRAME BY NUMBER | ||
| Syntax | QTFrame:<n> | Find the collected data associated with trace event number n. Trace events are numbered sequentially from zero. |
| Reply | F<x> | Frame x found. X may not be equal to n, if the frame buffer is circular and if the oldest frame in the buffer is older than n (in which case x will be the oldest frame). |
| F<x>T<y> | As above, but y is the tracepoint id associated with trace frame x (if the target can provide this information). | |
| F-1 | No corresponding trace frame found. | |
| "" | Empty packet: target does not support tracing. | |
| REQUEST TRACE FRAME BY PC | ||
| Syntax | QTFrame:pc:<addr> | Find the next collected data associated with a trace event at program counter "addr". |
| Reply | See replies for REQUEST FRAME BY NUMBER . | |
| REQUEST TRACE FRAME BY TRACEPOINT | ||
| Syntax | QTFrame:tdp:<n> | Find the next collected data associated with a trace event associated with tracepoint number n. |
| Reply | See replies for REQUEST FRAME BY NUMBER . | |
| REQUEST TRACE FRAME BY PC IN RANGE | ||
| Syntax | QTFrame:range:<start>:<stop> | Find the next collected data associated with a trace event associated with a program counter between "start" and "stop". |
| Reply | See replies for REQUEST FRAME BY NUMBER . | |
| REQUEST TRACE FRAME BY PC OUTSIDE RANGE | ||
| Syntax | QTFrame:outside:<start>:<stop> | Find the next collected data associated with a trace event associated with a program counter that isn't between "start" and "stop". |
| Reply | See replies for REQUEST FRAME BY NUMBER . | |