elf_cntl(3elf)

1elf_cntl(3ELF)               ELF Library Functions              elf_cntl(3ELF)
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NAME

6       elf_cntl - control an elf file descriptor
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SYNOPSIS

9       cc [ flag ... ] file ... -lelf [ library ... ]
10       #include <libelf.h>
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12       int elf_cntl(Elf *elf, Elf_Cmd cmd);
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DESCRIPTION

16       elf_cntl() instructs the library to modify its behavior with respect to
17       an ELF descriptor, elf. As elf_begin(3ELF) describes, an ELF descriptor
18       can have multiple activations, and multiple ELF descriptors may share a
19       single file descriptor. Generally, elf_cntl()  commands  apply  to  all
20       activations  of elf. Moreover, if the ELF descriptor is associated with
21       an archive file, descriptors for members within the archive  will  also
22       be  affected as described below. Unless stated otherwise, operations on
23       archive members do not affect the descriptor  for  the  containing  ar‐
24       chive.
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27       The  cmd argument tells what actions to take and may have the following
28       values:
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30       ELF_C_FDDONE    This value tells  the  library  not  to  use  the  file
31                       descriptor  associated  with  elf. A program should use
32                       this command when it has requested all the  information
33                       it  cares  to  use  and wishes to avoid the overhead of
34                       reading the rest of the file. The memory for  all  com‐
35                       pleted  operations remains valid, but later file opera‐
36                       tions, such as the initial elf_getdata() for a section,
37                       will fail if the data are not in memory already.
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40       ELF_C_FDREAD    This  command  is  similar  to  ELF_C_FDDONE, except it
41                       forces the library to read the rest of the file. A pro‐
42                       gram  should  use  this  command when it must close the
43                       file descriptor but has  not  yet  read  everything  it
44                       needs  from  the  file.  After elf_cntl() completes the
45                       ELF_C_FDREAD  command,  future  operations,   such   as
46                       elf_getdata(),  will use the memory version of the file
47                       without needing to use the file descriptor.
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51       If elf_cntl() succeeds, it returns 0. Otherwise  elf  was  NULL  or  an
52       error occurred, and the function returns −1.
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ATTRIBUTES

55       See attributes(5) for descriptions of the following attributes:
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60       ┌─────────────────────────────┬─────────────────────────────┐
61       │      ATTRIBUTE TYPE         │      ATTRIBUTE VALUE        │
62       ├─────────────────────────────┼─────────────────────────────┤
63       │Interface Stability          │Stable                       │
64       ├─────────────────────────────┼─────────────────────────────┤
65       │MT-Level                     │MT-Safe                      │
66       └─────────────────────────────┴─────────────────────────────┘
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NOTES

73       If the program wishes to use the ``raw'' operations (see elf_rawdata(),
74       which  elf_getdata(3ELF)  describes,  and elf_rawfile(3ELF)) after dis‐
75       abling the file descriptor with ELF_C_FDDONE or ELF_C_FDREAD,  it  must
76       execute  the  raw  operations explicitly beforehand. Otherwise, the raw
77       file operations will fail. Calling elf_rawfile() makes the entire image
78       available, thus supporting subsequent elf_rawdata() calls.
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82SunOS 5.11                        11 Jul 2001                   elf_cntl(3ELF)

NAME

SYNOPSIS

DESCRIPTION

ATTRIBUTES

SEE ALSO

NOTES