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(itstool) path: sect3/para
<literal>SIGSEGV</literal> indicates that the program tried to access memory (run code or read/write data usually) at a location that does not belong to it, but does not give any specifics. For that, look at the source code at line 10 of file temp2.c, in <function>bazz()</function>. The backtrace also says that in this case, <function>bazz()</function> was called from <function>main()</function>.
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Context English Portuguese (Brazil) State
That is not what was expected! Time to see what is going on! Isso não foi o que esperávamos! Hora de ver o que está acontecendo!
<prompt>%</prompt> <userinput>lldb -- temp</userinput>
(lldb) target create "temp"
Current executable set to 'temp' (x86_64).
(lldb) <userinput>breakpoint set -n main</userinput> <lineannotation>Skip the set-up code</lineannotation>
Breakpoint 1: where = temp`main + 15 at temp.c:8:2, address = 0x00000000002012ef <lineannotation>lldb puts breakpoint at main()</lineannotation>
(lldb) <userinput>process launch</userinput> <lineannotation>Run as far as main()</lineannotation>
Process 9992 launching
Process 9992 launched: '/home/pauamma/tmp/temp' (x86_64) <lineannotation>Program starts running</lineannotation>

Process 9992 stopped
* thread #1, name = 'temp', stop reason = breakpoint 1.1 <lineannotation>lldb stops at main()</lineannotation>
frame #0: 0x00000000002012ef temp`main at temp.c:8:2
5 main() {
6 int i;
7
-&gt; 8 printf("This is my program\n"); <lineannotation>Indicates the line where it stopped</lineannotation>
9 bazz(i);
10 return 0;
11 }
(lldb) <userinput>thread step-over</userinput> <lineannotation>Go to next line</lineannotation>
This is my program <lineannotation>Program prints out</lineannotation>
Process 9992 stopped
* thread #1, name = 'temp', stop reason = step over
frame #0: 0x0000000000201300 temp`main at temp.c:9:7
6 int i;
7
8 printf("This is my program\n");
-&gt; 9 bazz(i);
10 return 0;
11 }
12
(lldb) <userinput>thread step-in</userinput> <lineannotation>step into bazz()</lineannotation>
Process 9992 stopped
* thread #1, name = 'temp', stop reason = step in
frame #0: 0x000000000020132b temp`bazz(anint=-5360) at temp.c:14:29 <lineannotation>lldb displays stack frame</lineannotation>
11 }
12
13 int bazz(int anint) {
-&gt; 14 printf("You gave me %d\n", anint);
15 return anint;
16 }
(lldb)
Hang on a minute! How did <symbol>anint</symbol> get to be <literal>-5360</literal>? Was it not set to <literal>5</literal> in <function>main()</function>? Let us move up to <function>main()</function> and have a look. Espere um minuto! Como foi <symbol> não anint </symbol> chegar a ser <literal> 4231 </literal> ? Nós não definimos para sermos <literal> 5 </literal> dentro <function> a Principal() </function> ? Vamos subir para <function> a Principal() </function> e dê uma olhada.
(lldb) <userinput>up</userinput> <lineannotation>Move up call stack</lineannotation>
frame #1: 0x000000000020130b temp`main at temp.c:9:2 <lineannotation>lldb displays stack frame</lineannotation>
6 int i;
7
8 printf("This is my program\n");
-&gt; 9 bazz(i);
10 return 0;
11 }
12
(lldb) <userinput>frame variable i</userinput> <lineannotation>Show us the value of i</lineannotation>
(int) i = -5360 <lineannotation>lldb displays -5360</lineannotation> 		(gdb) <userinput>up</userinput> <lineannotation>Move up call stack</lineannotation>
#1 0x1625 in main () at temp.c:11 <lineannotation>gdb displays stack frame</lineannotation>
(gdb) <userinput>p i</userinput> <lineannotation>Show us the value of i</lineannotation>
$1 = 4231 <lineannotation>gdb displays 4231</lineannotation>
Oh dear! Looking at the code, we forgot to initialize <symbol>i</symbol>. We meant to put Oh querida! Olhando o código, esquecemos de inicializar <symbol> Eu </symbol> . Nós pretendíamos colocar
<lineannotation>…</lineannotation>
main() {
int i;

i = 5;
printf("This is my program\n");
<lineannotation>…</lineannotation> 		<lineannotation>…</lineannotation>
main() {
int i;

i = 5;
printf("This is my program\n");
<lineannotation>…</lineannotation>
but we left the <literal>i=5;</literal> line out. As we did not initialize <symbol>i</symbol>, it had whatever number happened to be in that area of memory when the program ran, which in this case happened to be <literal>-5360</literal>. mas deixamos o <literal> i = 5; </literal> line out. Como nós não inicializamos <symbol> Eu </symbol> , tinha qualquer número que estivesse naquela área de memória quando o programa rodava, o que neste caso aconteceu <literal> 4231 </literal>
The <command>lldb</command> command displays the stack frame every time we go into or out of a function, even if we are using <userinput>up</userinput> and <userinput>down</userinput> to move around the call stack. This shows the name of the function and the values of its arguments, which helps us keep track of where we are and what is going on. (The stack is a storage area where the program stores information about the arguments passed to functions and where to go when it returns from a function call.) <command> gdb </command> exibe o quadro da pilha toda vez que entramos ou saímos de uma função, mesmo se estivermos usando <command> acima </command> e <command> baixa </command> para percorrer a pilha de chamadas. Isso mostra o nome da função e os valores de seus argumentos, o que nos ajuda a saber onde estamos e o que está acontecendo. (A pilha é uma área de armazenamento onde o programa armazena informações sobre os argumentos passados ​​às funções e para onde ir quando retorna de uma chamada de função).
Examining a Core File with lldb Examinando um arquivo principal
A core file is basically a file which contains the complete state of the process when it crashed. In <quote>the good old days</quote>, programmers had to print out hex listings of core files and sweat over machine code manuals, but now life is a bit easier. Incidentally, under FreeBSD and other 4.4BSD systems, a core file is called <filename><replaceable>progname</replaceable>.core</filename> instead of just <filename>core</filename>, to make it clearer which program a core file belongs to. Um arquivo principal é basicamente um arquivo que contém o estado completo do processo quando ele caiu. <quote> os bons velhos tempos </quote> os programadores tiveram que imprimir listas hexadecimais de arquivos principais e suar os manuais de códigos de máquina, mas agora a vida é um pouco mais fácil. Aliás, sob o FreeBSD e outros sistemas 4.4BSD, um arquivo principal é chamado <filename><replaceable> progname </replaceable> .testemunho </filename> em vez de apenas <filename> testemunho </filename> , para tornar mais claro qual programa um arquivo principal pertence.
To examine a core file, specify the name of the core file in addition to the program itself. Instead of starting up <command>lldb</command> in the usual way, type <userinput>lldb -c <replaceable>progname</replaceable>.core -- <replaceable>progname</replaceable></userinput>
The debugger will display something like this: O script pode ser algo como isto:
<prompt>%</prompt> <userinput>lldb -c <filename><replaceable>progname</replaceable>.core</filename> -- <filename><replaceable>progname</replaceable></filename></userinput>
(lldb) target create "<filename><replaceable>progname</replaceable></filename>" --core "<filename><replaceable>progname</replaceable></filename>.core"
Core file '/home/pauamma/tmp/<filename><replaceable>progname</replaceable>.core</filename>' (x86_64) was loaded.
(lldb)
In this case, the program was called <filename><replaceable>progname</replaceable></filename>, so the core file is called <filename><replaceable>progname</replaceable>.core</filename>. The debugger does not display why the program crashed or where. For this, use <userinput>thread backtrace all</userinput>. This will also show how the function where the program dumped core was called.
(lldb) <userinput>thread backtrace all</userinput>
* thread #1, name = '<filename><replaceable>progname</replaceable></filename>', stop reason = signal SIGSEGV
* frame #0: 0x0000000000201347 <filename><replaceable>progname</replaceable></filename>`bazz(anint=5) at temp2.c:17:10
frame #1: 0x0000000000201312 <filename><replaceable>progname</replaceable></filename>`main at temp2.c:10:2
frame #2: 0x000000000020110f <filename><replaceable>progname</replaceable></filename>`_start(ap=&lt;unavailable&gt;, cleanup=&lt;unavailable&gt;) at crt1.c:76:7
(lldb)
<literal>SIGSEGV</literal> indicates that the program tried to access memory (run code or read/write data usually) at a location that does not belong to it, but does not give any specifics. For that, look at the source code at line 10 of file temp2.c, in <function>bazz()</function>. The backtrace also says that in this case, <function>bazz()</function> was called from <function>main()</function>.
Attaching to a Running Program with lldb Anexando a um programa em execução
One of the neatest features about <command>lldb</command> is that it can attach to a program that is already running. Of course, that requires sufficient permissions to do so. A common problem is stepping through a program that forks and wanting to trace the child, but the debugger will only trace the parent. Uma das características mais interessantes sobre <command> gdb </command> é que ele pode se conectar a um programa que já está em execução. Claro, isso pressupõe que você tenha permissões suficientes para isso. Um problema comum é quando você está percorrendo um programa que se bifurca e deseja rastrear o filho, mas o depurador só permitirá rastrear o pai.
To do that, start up another <command>lldb</command>, use <command>ps</command> to find the process ID for the child, and do O que você faz é iniciar outra <command> gdb </command> , usar <command> ps </command> para encontrar o ID do processo para o filho e fazer
(lldb) <userinput>process attach -p <replaceable>pid</replaceable></userinput> (gdb) <userinput>attach <replaceable>pid</replaceable></userinput>
in <command>lldb</command>, and then debug as usual. dentro <command> gdb </command> e, em seguida, depurar como de costume
For that to work well, the code that calls <function>fork</function> to create the child needs to do something like the following (courtesy of the <command>gdb</command> info pages):
<lineannotation>…</lineannotation>
if ((pid = fork()) &lt; 0) /* _Always_ check this */
error();
else if (pid == 0) { /* child */
int PauseMode = 1;

while (PauseMode)
sleep(10); /* Wait until someone attaches to us */
<lineannotation>…</lineannotation>
} else { /* parent */
<lineannotation>…</lineannotation> 		<lineannotation>…</lineannotation>
if ((pid = fork()) &lt; 0) /* _Always_ check this */
error();
else if (pid == 0) { /* child */
int PauseMode = 1;

while (PauseMode)
sleep(10); /* Wait until someone attaches to us */
<lineannotation>…</lineannotation>
} else { /* parent */
<lineannotation>…</lineannotation>
Now all that is needed is to attach to the child, set <symbol>PauseMode</symbol> to <literal>0</literal> with <userinput>expr PauseMode = 0</userinput> and wait for the <function>sleep()</function> call to return. Agora tudo que você tem a fazer é anexar à criança, definir <symbol> PauseMode </symbol> para <literal> 0 </literal> e aguarde o <function> dormir() </function> ligue para voltar!
Remote Debugging Using LLDB Depuração do Kernel On-Line Usando o DDB
The described functionality is available starting with LLDB version 12.0.0. Users of FreeBSD releases containing an earlier LLDB version may wish to use the snapshot available in <link xlink:href="@@URL_RELPREFIX@@/doc/en_US.ISO8859-1/books/handbook/ports-using.html">ports or packages</link>, as <package>devel/llvm-devel</package>.
Starting with LLDB 12.0.0, remote debugging is supported on FreeBSD. This means that <command>lldb-server</command> can be started to debug a program on one host, while the interactive <command>lldb</command> client connects to it from another one.
To launch a new process to be debugged remotely, run <command>lldb-server</command> on the remote server by typing
<prompt>%</prompt> <userinput>lldb-server g <replaceable>host:port</replaceable> -- <replaceable>progname</replaceable></userinput> <prompt>%</prompt> <userinput>comm -23 ../<replaceable>old</replaceable> ../<replaceable>new</replaceable></userinput>
The process will be stopped immediately after launching, and <command>lldb-server</command> will wait for the client to connect.
Start <command>lldb</command> locally and type the following command to connect to the remote server:

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English Portuguese (Brazil)
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Source information

Source string comment
(itstool) path: sect3/para
Source string location
book.translate.xml:1989
String age
5 months ago
Source string age
5 months ago
Translation file
books/pt_BR/developers-handbook.po, string 356