Databases
StackOverflow2013
Postsdbo
POtwo mallocs returning same pointer value
 

Note that there are some explanatory texts on larger screens.

plurals
  1. POtwo mallocs returning same pointer value
    primarykey
    data
    text
    <p>I'm filling a structure with data from a line, the line format could be 3 different forms:<br> 1.-"LD "(Just one word)<br> 2.-"LD A "(Just 2 words)<br> 3.- "LD A,B "(The second word separated by a coma).<br> The structure called instruccion has only the 3 pointers to point each part (<code>mnemo</code>, <code>op1</code> and <code>op2</code>), but when allocating memory for the second word sometimes <code>malloc</code> returns the same value that was given for the first word. Here is the code with the <code>mallocs</code> pointed:</p> <pre><code>instruccion sepInst(char *linea){ instruccion nueva; char *et; while(linea[strlen(linea)-1]==32||linea[strlen(linea)-1]==9)//Eliminating spaces and tabs at the end of the line linea[strlen(linea)-1]=0; et=nextET(linea);//Save the direction of the next space or tab if(*et==0){//If there is not, i save all in mnemo nueva.mnemo=malloc(strlen(linea)+1); strcpy(nueva.mnemo,linea); nueva.op1=malloc(2); nueva.op1[0]='k';nueva.op1[1]=0;//And set a "K" for op1 nueva.op2=NULL; return nueva; } nueva.mnemo=malloc(et-linea+1);&lt;----------------------------------- strncpy(nueva.mnemo,linea,et-linea); nueva.mnemo[et-linea]=0;printf("\nj%xj",nueva.mnemo); linea=et; while(*linea==9||*linea==32)//Move pointer to the second word linea++; if(strchr(linea,',')==NULL){//Check if there is a coma nueva.op1=malloc(strlen(linea)+1);//Do this if there wasn't any coma strcpy(nueva.op1,linea); nueva.op2=NULL; } else{//Do this if there was a coma nueva.op1=malloc(strchr(linea,',')-linea+1);&lt;---------------------------------- strncpy(nueva.op1,linea,strchr(linea,',')-linea); nueva.op1[strchr(linea,',')-linea]=0; linea=strchr(linea,',')+1; nueva.op2=malloc(strlen(linea)+1); strcpy(nueva.op2,linea);printf("\n2j%xj2",nueva.op2); } return nueva; } </code></pre> <p>When I print the pointers it happens to be the same number. note: the function char *nextET(char *line) returns the direction of the first space or tab in the line, if there is not it returns the direction of the end of the line.</p> <p><code>sepInst()</code> is called several times in a program and only after it has been called several times it starts failing. These <code>mallocs</code> across all my program are giving me such a headache.</p>
    singulars
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PTQuestion
    1. USEitan T
    1. USMark E
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PO
      singulars
      1. PTAnswer
    2. PO
      singulars
      1. PTAnswer
    1. VO
      singulars
      1. POtwo mallocs returning same pointer value
      1. This table or related slice is empty.
      1. VTApproveEditSuggestion
    1. COThis is far too much code for a SO question. Please construct a 10-line [minimal test case](http://sscce.org), preferably in English...
      singulars
      1. POtwo mallocs returning same pointer value
      1. USOliver Charlesworth
    2. COSorry i don't know how to do a small example cause i don't know exactly where is the problem in the function but i translated the comments to be in english
      singulars
      1. POtwo mallocs returning same pointer value
      1. USMark E
    3. COStart by removing everything that is not necessary (all the lines that after removing them, you still observe the same behavior you mentioned in your question).
      singulars
      1. POtwo mallocs returning same pointer value
      1. USbetabandido
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload