Last login: Wed Sep 28 22:19:34 on ttys003
cd/Users/ericperez/.zshrc:export:18: not valid in this context: Plug-Ins/JavaAppletPlugin.plugin/Contents/Home
(base) ericperez@MacBook-Pro-de-Eric-2 ~ % cd Desktop  
(base) ericperez@MacBook-Pro-de-Eric-2 Desktop % gcc -g -o prog prog.c
clang: error: no such file or directory: 'prog.c'
clang: error: no input files
(base) ericperez@MacBook-Pro-de-Eric-2 Desktop % gdb ./prog
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Reading symbols from ./prog...
Reading symbols from /Users/ericperez/Desktop/prog.dSYM/Contents/Resources/DWARF/prog...
(gdb) run
Starting program: /Users/ericperez/Desktop/prog 
[New Thread 0x1f03 of process 1158]
[New Thread 0x1903 of process 1158]
[New Thread 0x1c03 of process 1158]
warning: unhandled dyld version (17)
Khoor#zruog1

Thread 3 received signal SIGSEGV, Segmentation fault.
0x0000000100003ef7 in affiche (message=0x0) at prog.c:7
warning: Source file is more recent than executable.
7	        printf("%c", (*message)+i);
(gdb) c
Continuing.

Program terminated with signal SIGSEGV, Segmentation fault.
The program no longer exists.
(gdb) c
The program is not being run.
(gdb) run
Starting program: /Users/ericperez/Desktop/prog 
[New Thread 0x1f13 of process 1160]
[New Thread 0x1a03 of process 1160]
[New Thread 0x2a03 of process 1160]
warning: unhandled dyld version (17)
Khoor#zruog1

Thread 3 received signal SIGSEGV, Segmentation fault.
0x0000000100003ef7 in affiche (message=0x0) at prog.c:7
7	        printf("%c", (*message)+i);
(gdb) backtrace
#0  0x0000000100003ef7 in affiche (message=0x0) at prog.c:7
#1  0x0000000100003f74 in main () at prog.c:18
(gdb) c
Continuing.

Program terminated with signal SIGSEGV, Segmentation fault.
The program no longer exists.
(gdb) break main
Breakpoint 1 at 0x100003f4f: file prog.c, line 15.
(gdb) run
Starting program: /Users/ericperez/Desktop/prog 
[New Thread 0x1f23 of process 1163]
[New Thread 0x2c03 of process 1163]
[New Thread 0x5403 of process 1163]
warning: unhandled dyld version (17)

Thread 3 hit Breakpoint 1, main () at prog.c:15
15	    char * mess1 = NULL;
(gdb) next
16	    char * mess2 = "Hello world.";
(gdb) print mess1
$1 = 0x0
(gdb) next
17	    affiche(mess2);
(gdb) next
Khoor#zruog1
18	    affiche(mess1);
(gdb) step
affiche (message=0x0) at prog.c:5
5	    int i = 3;
(gdb) step
7	        printf("%c", (*message)+i);
(gdb) step

Thread 3 received signal SIGSEGV, Segmentation fault.
0x0000000100003ef7 in affiche (message=0x0) at prog.c:7
7	        printf("%c", (*message)+i);
(gdb) print (*message)+i
Cannot access memory at address 0x0
(gdb)