lug-bg: C/C++ + binary executable file

2004-09-30 Thread Aleksander Valchev 
(/++)
   binary 
executable?
 file(1).  `man file` ,  
 binary 
executable   magic number 
  
   . 
  ...

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Re: lug-bg: C/C++ + binary executable file

2004-09-30 Thread Vasil Kolev 
 , 2004-09-30  12:33, Aleksander Valchev :
 (/++)   
 binary 
 executable?
  file(1).  `man file` ,  
  binary 
 executable   magic number 
   
. 
   ...

  , magic (man 5 magic), 
 
/usr/share/misc/magic,   
 ,
  file   . 
   
   source  file
,   
.

 ELF executable,   
, 
 googleELF executable format.


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Re: lug-bg: C/C++ + binary executable file

2004-09-30 Thread Peter Pentchev 
On Thu, Sep 30, 2004 at 12:53:24PM +0300, Vasil Kolev wrote:
  , 2004-09-30  12:33, Aleksander Valchev :
  (/++)   binary 
  executable?
   file(1).  `man file` ,   binary 
  executable   magic number   
 .   ...
 
   , magic (man 5 magic),  
 /usr/share/misc/magic,,
   file   .
source  file,   
 .
 
  ELF executable,   , 
  googleELF executable format.

  ,   
ELF0x7F,
'E', 'L', 'F'.   magic-  file(1),
  file(1),  
  magic, ELF,  ,   :)

,


-- 
Peter Pentchev  [EMAIL PROTECTED][EMAIL PROTECTED][EMAIL PROTECTED]
PGP key:http://people.FreeBSD.org/~roam/roam.key.asc
Key fingerprint FDBA FD79 C26F 3C51 C95E  DF9E ED18 B68D 1619 4553
What would this sentence be like if pi were 3?


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Re: lug-bg: C/C++ + binary executable file

2004-09-30 Thread 
 12:33:23pm +0300  30  2004, Aleksander Valchev :
 (/++)   
 binary 
 executable?
  file(1).  `man file` ,  
  binary 
 executable   magic number 
   
. 
   ...

,   

  ELF[1]. 
  
 ,
[2].   
   :)


[1] http://www.caldera.com/developers/gabi
[2] http://www.caldera.com/developers/gabi/latest/ch4.eheader.html#elfid


,

-- 
Linux is for those who hate Windows.
FreeBSD is for those who love UNIX.
#include stdio.h
#include unistd.h
#include fcntl.h
#include elf.h


int check_elf(int fd)
{
 Elf_Ehdr ehdr;
 int ret;
 
 ret = read(fd, ehdr, sizeof(Elf_Ehdr));
 if(ret == -1 || ret  sizeof(Elf_Ehdr))
  return -1;

 if(ehdr.e_ident[EI_MAG0] != ELFMAG0 ||
ehdr.e_ident[EI_MAG1] != ELFMAG1 ||
ehdr.e_ident[EI_MAG2] != ELFMAG2 ||
ehdr.e_ident[EI_MAG3] != ELFMAG3)
  return -1;

 return 0;
}

int main(int argc, char **argv)
{
 char *files[] = { /bin/ls, /etc/motd };
 int fd;
 
 fd = open(files[0], O_RDONLY);
 if(fd == -1)
  return 1;

 if(check_elf(fd) == -1)
  printf(%s: not an ELF executable\n, files[0]);
 else
  printf(%s: an ELF executable\n, files[0]);

 close(fd);


 fd = open(files[1], O_RDONLY);
 if(fd == -1)
  return 1;

 if(check_elf(fd) == -1)
  printf(%s: not an ELF executable\n, files[1]);
 else
  printf(%s: an ELF executable\n, files[1]);

 close(fd);
 
 return 0;
}