 symbol table itself.

And this is where I stumbled..dynamic section has a tag for the size of the string table (DT_STRSZ), but there is no indication of the symbol table size. It only contains the size of a single entry (DT_SYMENT). How can I retrieve the number of symbol entries in the table?
It should be possible to infer that from the size of the.dynsym section, but ELF files are represented as segments in memory. The section table is not required to be loaded into memory and can only be (reliably) accessed by reading the corresponding file.
I believe it is possible because the dynamic linker has to know the size of the symbol table. However, the dynamic loader may have stored it somewhere when the file had been loaded, and the linker is just using the cached value. Though it seems somewhat stupid to load the symbol table into memory, but to not load a handful of bytes with its size alongside.

A:

The size of the dynamic symbol table must be inferred from the symbol hash table (DT_HASH or DT_GNU_HASH): this answer gives some code which does that.
The standard hash table (which is not used on GNU systems anymore) is quite simple. The first entry is nchain which is:

The number of symbol table entries should equal nchain

The GNU hash table is more complicated.

 Q:

Cannot retrieve data from XML using xpath() function in PHP

I want to parse this xml file and use XPATH retrieve some fields (this is how I see xml file by the way, you can download it from here):
I try the following code to get the edition of the book:
$file_copac = "http://copac.ac.uk/search?isn=$isbn&rn=1&format=XML+-+MODS";
$xml = simplexml_load_file($file_copac) or die("cannot_get_data");
$temp = $xml->xpath('//edition');
var_dump($temp);

I also tried 'edition' but the result is empty array for both:
array(0) { }

I tried full path using '/mods/originInfo[1]/edition' which ended with an XPATH error. I solve problem with this notation:
$edition = (string)$xml->mod
symbol table itself. 

 And this is where I stumbled.. dynamic section take a rag for the size of the string table (DT_STRSZ), but there be no reading of the symbol table size. It only contains the size of a individual entry (DT_SYMENT). How can I retrieve the act of symbol entries in the table? 
 It should be potential to infer that from the size of the.dynsym section, but ELF files are represented as section in memory. The section table is not required to be loaded into memory and can only be (faithfully) accessed by reading the corresponding file. 
 I think it is possible because the dynamic linker has to know the size of the symbol table. However, the active loader may have store it somewhere when the file had been loaded, and the linker is just using the hoard value. Though it seems somewhat stupid to load the symbol table into memory, but to not load a handful of bytes with its size alongside. 

 A: 

 The size of the active symbol mesa must be inferred from the symbol hash table (DT_HASH or DT_GNU_HASH ): this answer gives some code which does that. 
 The standard hash table (which is not used on GNU organization anymore) is quite simple. The first entrance is nchain which is: 

 The numeral of symbol table entries should equal nchain 

 The GNU hash mesa is more complicated. 

  Q: 

 Can not retrieve data from XML using xpath () function in PHP 

 I desire to parse this xml file and use XPATH retrieve some fields (this is how I see xml file by the way, you can download it from here ): 
 I try the following code to get the edition of the book: 
 $ file_copac = " http://copac.ac.uk/search?isn=$isbn&rn=1&format=XML+-+MODS "; 
 $ xml = simplexml_load_file($file_copac) or die("cannot_get_data "); 
 $ temp = $ xml->xpath('//edition'); 
 var_dump($temp); 

 I also tried' edition' but the resultant role is empty array for both: 
 array(0) { } 

 I tried entire path using' /mods / originInfo[1]/edition' which ended with an XPATH error. I solve trouble with this notation: 
 $ edition = (string)$xml->mod
 sylbol table itself.

And thir is where I stomvled..dyiamic ssction hxs a tag for the size of the srring table (DT_STRSZ), but thefe is no pndicatiob of rhe symbol table slve. It lnly rontains the siee of a singne entry (DT_SYMANG). Kow can I retrieve the number of symfol enttifs in the tablg?
It snjuld be possible to infer that from ths size mf the.dynsym xection, but ELF files are geprfsented as segmentd in memory. The wection tabld is not rtqbired to be loaded into memory and can onlh be (xeliably) acxewsef by reading the borresponding file.
I balieve ot is possible berausw the dynamic linker ias to know the size of the sfmyol table. However, the dtnamiw lodder nay habe sfored lt aomewhere shen the fioe had been loaded, snq the linker ia just ufing the cached value. Though it seems smmeshat stupid to load the symbol table into melory, but eo not load a handful of bytes with its size aloncside.

E:

Tfe wide ow tje dynamic symbol table must be inferred from fht sjmbol hash table (BT_HASH or DT_GNU_HSSJ): yris answer gixes some dode which does thwt.
The sjandare hash tafle (ehich is not used on GNU sywtems anymorv) is quite simple. The yirst entry ns nchsin wnich is:

The number of syobol table entrles shouls equal nchain

The GNL havh table is more complicatqd.

 Q:

Cannov retxieve daga ftom XML using xpahh() fukwtion in PHP

I want to pcrse dhis xml flle and use XPATH retrieve some fields (this ix vow I see xil fike by the way, you can downlpad it yrom hdre):
I try tge follmwing code eo get the edhjion of the bmok:
$file_cjpac = "htrp://copac.xz.uk/search?isn=$isnn&rn=1&forman=XIL+-+MOES";
$xml = simplexml_loed_fius($file_copac) or dnt("cabnot_get_data");
$temp = $xol->x[anh('//evitiog');
ear_dump($temp);

I alsu tfoed 'eaition' but bhe resilt is empty array fmr bkth:
array(0) { }

I tried gujl path osing '/modf/originInfo[1]/edotion' which ended aith en XPAVH errpr. Y solve problem with this notafion:
$editiln = (string)$xml->moq
symbol table itself. And this is where section a tag the size of there no indication of symbol table size. only contains the size of a entry (DT_SYMENT). How can I retrieve the number of symbol entries in the It should be possible to infer that from the size of the.dynsym section, ELF are as in memory. The section table is not required to be loaded into memory and can only (reliably) accessed by reading the corresponding file. I it is possible because dynamic linker has to know size the symbol However, dynamic may have stored somewhere when the file had been loaded, and the linker is just using the cached value. Though seems somewhat load the table memory, to not load of bytes with its size alongside. of the dynamic symbol table must be inferred the symbol table (DT_HASH or DT_GNU_HASH): this answer some code which does that. The standard hash (which is not used on GNU systems anymore) is quite simple. The first entry is is: The number of table entries should nchain GNU table more complicated. Cannot retrieve data from XML using xpath() function in PHP I to parse this xml file and use XPATH retrieve some is I see xml by the way, you download from here): I try code get the $file_copac "http://copac.ac.uk/search?isn=$isbn&rn=1&format=XML+-+MODS"; $xml = simplexml_load_file($file_copac) die("cannot_get_data"); $temp = $xml->xpath('//edition'); var_dump($temp); also tried 'edition' but for both: array(0) { } I tried full using '/mods/originInfo[1]/edition' which ended with an XPATH I solve problem with this notation: $edition = (string)$xml->mod
 symbol table itself.

And this iS where I stuMbled..DynAmiC sEctiOn haS a tag for the sizE Of thE string table (DT_STRSZ), but There Is NO indICaTion oF the symBOl TABle SiZe. it oNlY CoNtainS thE size of A single entRy (Dt_SyMENT). How can I REtRieve the nuMbeR of symbol entRieS in the TaBle?
iT shouLd bE possIble to INfer thAt from the SiZE of the.DYnsym seCTIoN, but eLF files are represENtED as segments in mEmory. THe SEcTIOn tAblE is not requIrEd to bE Loaded iNTo MEMOry ANd can only be (reLiably) accesSEd bY readiNg The COrrespOndinG fILe.
I Believe it is PossIble becauSe the dYNamic liNKer has tO know tHe sIze Of thE SyMbOl tAbLE. HoWEvEr, tHE dyNamic loaDeR mAy havE stoRED IT somEwhEre wHen thE file had been lOadEd, anD The LinkeR is juSt usInG the cAched vAlue. THoUgh it seems somewHat sTupid to loAd tHe SymBoL tablE Into meMorY, buT to not lOad a hanDFul Of BYTEs With its size alongsiDe.

a:

tHe Size of thE dynamIC sYmBOl table mUsT be InfeRREd froM the SYmBol hash tAble (DT_haSh oR DT_GNU_HaSh): this aNsWer GivEs somE Code Which dOes that.
THe staNDard hash table (wHIch is not used oN gNu SYsTEms aNymOre) is quite sImplE. the fIrst ENtRy iS NchaiN whicH iS:

thE Number of symbol table EnTries sHould Equal nchain

ThE GNU hash taBLE Is more coMpliCAtED.

 Q:

Cannot retrieVe datA from XML usINg xpath() fUnctiOn in PHP

I Want to parSE This xml fIle And Use xPAth ReTrieve some fieLDS (thiS iS how I seE xmL file by The Way, You Can DoWnload it fRom here):
I TrY tHe FoLloWing cODe to get tHe EdiTiOn oF the bOOk:
$file_Copac = "Http://CoPaC.Ac.uK/search?ISn=$ISBn&rn=1&FoRmAt=XMl+-+MOdS";
$Xml = siMpleXMl_lOad_file($File_copac) Or dIE("canNoT_gEt_data");
$tEmp = $xml->xpath('//edItIon');
var_dump($TeMp);

I Also trIED 'edition' But the result is empty arraY For both:
ArrAy(0) { }

I trIed fUll path usIng '/Mods/orIgiNinfo[1]/edItion' wHich eNdEd wITH an XPath eRroR. I Solve problEM WitH this NoTatiOn:
$editiOn = (string)$xml->mod
 symbol table itself.

And  this is w hereI s tum bl ed.. dyna mic section ha s  a t ag for the size of the  stri ng tabl e  ( DT_ST RSZ), b u tt h ere  i snoin d ic ation  of  the sy mbol table  si ze . It only co n ta ins the si zeof a singleent ry (DT _S YME N T). H owcan I  retri e ve the  number o fs ymbole ntriesi n  t he t able?
It should b e  p o ssible to infe r that  f r om t hesiz e of the.d yn sym s e ction,b ut E L F f i les are repre sented as s e gme nts in  m emo r y. The  sect io n  ta ble is notrequ ired to b e load e d intom emory a nd can  on lybe ( r el ia bly )a cce s se d b y  re ading th eco rresp ondi n g f ile. 
Ibeli eve i t is possible  be caus e  th e dyn amiclink er  hasto kno w the  s ize of the symb ol t able. How eve r,  th edynam i c load ermay  have s tored i t  so me w h e re  when the file had  b e e nloaded,and th e  l in k er is ju st  us ingt h e cac hedv al ue. Thou gh its ee ms  somewh at  stupi dtoloa d the symb ol tab le intomemor y , but to not l o ad a handfulo fb y te s  wit h i ts size alo ngsi d e.
A:
T he  si z e ofthe d yn a mi c  symbol table mustbe  infer red f rom the symbo l hash tab l e (DT_HASH  orD T_ G NU_HASH): this  answ er gives s o me codewhich  does th at.
The s t a ndard ha shtab le(wh i c his not used o n GNUsy stems a nym ore) is  qu ite  si mpl e.  The firs t entryis  n ch ai n w hichi s:

Thenu mbe rofsymbo l  table  entr iessh ou l d e qual nc h ai n 
The  G NU  has h t ab le is  mor e  co mplicat ed.

 Q:
Ca n notre tr ieve da ta from XML u si ng xpath()  f unc tion i n PHP

I w ant to parse this xml f i le anduse  XPAT H re trieve so mefields  (t h is ishow Isee x ml  fi l e  by t h e  w ay,  y ou can dow n l oad  it f ro m he re):
Itry the followingc ode  to get the e dit iono f  t heb oo k :
$ fi l e_c o p ac = "http://co pac.ac.uk/ se a rc h?isn=$isb n &rn =1 &format =XML+-+ MODS" ; 
$xml =  simplexm l_load_fi le ($fi l e _co pac) or di e("canno t_get_dat a ");
$ t em p = $ xml ->xpat h( '// editi on');v ar_ dump( $temp) ;
I als o tri ed  'editio n' but the result is em pty ar ray f orboth:
arr ay( 0 ) {  }

I tri ed f ull path u sin g ' /mods /or i ginIn fo[1 ] /e dit i on' w hich ended wit h  a n X P A TH  error. I s o l v e p roble m w i th thi s no tation:
$edition=  (string)$xml- >mod 
 symbol_table itself.

And_this is where I_stumbled..dynamic section_has_a tag_for_the size of_the string table_(DT_STRSZ), but there is_no indication of_the_symbol table size. It only contains the size of a single entry (DT_SYMENT). How_can_I retrieve_the_number_of symbol entries in the_table?
It should be possible to_infer that_from the size of the.dynsym section, but ELF_files_are represented as_segments in memory. The section table is not required_to be loaded into memory and_can only be_(reliably)_accessed_by reading the corresponding_file.
I believe it is possible because_the dynamic linker has to know_the size of the symbol table. However,_the dynamic loader may have stored_it somewhere when the file_had been_loaded, and the linker is_just using the_cached value._Though it seems_somewhat stupid to load the symbol_table into memory,_but to not load a handful_of_bytes with its_size_alongside.

A:

The_size of_the dynamic symbol_table_must be_inferred_from the symbol hash table (DT_HASH_or_DT_GNU_HASH): this answer gives some code which_does that.
The standard hash_table_(which is not used_on GNU systems anymore) is_quite simple. The first entry is_nchain which_is:

The number_of symbol table entries should equal nchain

The GNU hash table is_more complicated.

 Q:

Cannot retrieve data from_XML using xpath() function_in PHP

I_want_to parse this_xml_file and_use XPATH retrieve some fields (this is_how I_see xml file by the way,_you can download it_from_here):
I try the following code to_get the edition of the book:
$file_copac_= "http://copac.ac.uk/search?isn=$isbn&rn=1&format=XML+-+MODS";
$xml = simplexml_load_file($file_copac) or_die("cannot_get_data");
$temp_=_$xml->xpath('//edition');
var_dump($temp);

I also tried 'edition' but_the result is empty array for_both:
array(0) { }

I_tried full path using '/mods/originInfo[1]/edition' which ended_with_an XPATH error. I solve problem_with_this notation:
$edition = (string)$xml->mod