BEFORE SYSCALL -------------- (gdb) info registers r0 0x66 102 r1 0x7fcde360 2144199520 r2 0x100ce3e0 269280224 r3 0xf 15 r4 0x7fcde374 2144199540 r5 0x42 66 r6 0x7fcde3b0 2144199600 r7 0x7fcde3d0 2144199632 r8 0x7f7f7f7f 2139062143 r9 0x7fcde3d0 2144199632 r10 0x74000000 1946157056 r11 0xce6c23c8 3463193544 r12 0xd6138000 3591602176 r13 0x100cd358 269275992 r14 0x100c0000 269221888 r15 0x100cceb0 269274800 r16 0x0 0 r17 0xffffffff 4294967295 r18 0x10060000 268828672 r19 0x0 0 r20 0x100002cc 268436172 r21 0x100c0000 269221888 r22 0x1002a0d0 268607696 r23 0x1002a198 268607896 r24 0x0 0 r25 0x7fcde6b4 2144200372 r26 0x2 2 r27 0x7fcde76c 2144200556 r28 0x0 0 r29 0x100c0000 269221888 r30 0xff5ae5c 267759196 r31 0x7fcde390 2144199568 pc 0x1004990c 268736780 ps 0xd032 53298 cr 0x22000024 570425380 lr 0x100027a0 268445600 ctr 0xc011d7dc 3222394844 xer 0x0 0 fpscr 0x0 0 vscr 0x0 0 vrsave 0x0 0 (gdb) print ((int *)0x7fcde374)[0] $16 = 6 (gdb) print ((int *)0x7fcde374)[1] $17 = 0 (gdb) print ((int *)0x7fcde374)[2] $18 = 66 (gdb) print /x ((int *)0x7fcde374)[3] $19 = 0x7fdf03b0 (gdb) print /x ((int *)0x7fcde374)[4] $20 = 0x7fdf03d0 # r0 is syscall number (_NR_socketcall = 102) # r1 is stack pointer # r2 -- NOT USED # r3 is socket call type (SYS_GETSOCKOPT = 15) # r4 points to remainder of args # fd = sockfd = 6 # level = IPPROTO_IP = 0 # optname = IPT_SO_GET_REVISION_MATCH = 66 # optval = &rev = 0x7fa3b3b0 # optlen = &s = 0x7fa3b3d0 AFTER SYSCALL ------------- (gdb) info registers r0 0x0 0 r1 0x7fcde390 2144199568 r2 0x100ce3e0 269280224 r3 0x2 2 r4 0x100027a0 268445600 r5 0x32000024 838860836 r6 0xfffffffe 4294967294 r7 0x10049910 268736784 r8 0xd432 54322 r9 0x0 0 r10 0x1032 4146 r11 0x32000024 838860836 r12 0xd6138000 3591602176 r13 0x100cd358 269275992 r14 0x100c0000 269221888 r15 0x100cceb0 269274800 r16 0x0 0 r17 0xffffffff 4294967295 r18 0x10060000 268828672 r19 0x0 0 r20 0x100002cc 268436172 r21 0x100c0000 269221888 r22 0x1002a0d0 268607696 r23 0x1002a198 268607896 r24 0x0 0 r25 0x7fcde6b4 2144200372 r26 0x2 2 r27 0x7fcde76c 2144200556 r28 0x0 0 r29 0x100c0000 269221888 r30 0xff5ae5c 267759196 r31 0x7fcde390 2144199568 pc 0x10049914 268736788 ps 0xd032 53298 cr 0x32000024 838860836 lr 0x100027a0 268445600 ctr 0xc0011f90 3221299088 xer 0x20000000 536870912 fpscr 0x0 0 vscr 0x0 0 vrsave 0x0 0 # r3 has return value (ENOENT = 2)