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<?php $sp = fopen("php://memory", 'w+'); fseek($sp, 1024); // fails why? echo fwrite($sp, "abc"); // 3 fseek($sp, 1024); // echo fread($sp, 3); // NULL.. $sp = fopen("/tmp/foo", 'w+'); fseek($sp, 1024); echo fwrite($sp, "abc"); // 3 fseek($sp, 1024); echo fread($sp, 3); // abc
Finding entry points
Branch analysis from position: 0
1 jumps found. (Code = 62) Position 1 = -2
filename:       /in/LSLAi
function name:  (null)
number of ops:  47
compiled vars:  !0 = $sp
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    2     0  E >   INIT_FCALL                                               'fopen'
          1        SEND_VAL                                                 'php%3A%2F%2Fmemory'
          2        SEND_VAL                                                 'w%2B'
          3        DO_ICALL                                         $1      
          4        ASSIGN                                                   !0, $1
    3     5        INIT_FCALL                                               'fseek'
          6        SEND_VAR                                                 !0
          7        SEND_VAL                                                 1024
          8        DO_ICALL                                                 
    4     9        INIT_FCALL                                               'fwrite'
         10        SEND_VAR                                                 !0
         11        SEND_VAL                                                 'abc'
         12        DO_ICALL                                         $4      
         13        ECHO                                                     $4
    5    14        INIT_FCALL                                               'fseek'
         15        SEND_VAR                                                 !0
         16        SEND_VAL                                                 1024
         17        DO_ICALL                                                 
    6    18        INIT_FCALL                                               'fread'
         19        SEND_VAR                                                 !0
         20        SEND_VAL                                                 3
         21        DO_ICALL                                         $6      
         22        ECHO                                                     $6
    8    23        INIT_FCALL                                               'fopen'
         24        SEND_VAL                                                 '%2Ftmp%2Ffoo'
         25        SEND_VAL                                                 'w%2B'
         26        DO_ICALL                                         $7      
         27        ASSIGN                                                   !0, $7
    9    28        INIT_FCALL                                               'fseek'
         29        SEND_VAR                                                 !0
         30        SEND_VAL                                                 1024
         31        DO_ICALL                                                 
   10    32        INIT_FCALL                                               'fwrite'
         33        SEND_VAR                                                 !0
         34        SEND_VAL                                                 'abc'
         35        DO_ICALL                                         $10     
         36        ECHO                                                     $10
   11    37        INIT_FCALL                                               'fseek'
         38        SEND_VAR                                                 !0
         39        SEND_VAL                                                 1024
         40        DO_ICALL                                                 
   12    41        INIT_FCALL                                               'fread'
         42        SEND_VAR                                                 !0
         43        SEND_VAL                                                 3
         44        DO_ICALL                                         $12     
         45        ECHO                                                     $12
         46      > RETURN                                                   1

Generated using Vulcan Logic Dumper, using php 8.0.0


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