Solved

strtok help

Posted on 2001-07-10
7
625 Views
Last Modified: 2008-02-01
if i have

char szText[] = "test?blah?123";

and i want to use strtok to seperate the text on the ? and i want to assign each segment to a 100 byte buffer in

char *pszBuffer;
pszBuffer = malloc (10 * 100);

how would i do it with strtok? i cant figure it out.
0
Comment
Question by:Kitty__Kong
7 Comments
 
LVL 2

Accepted Solution

by:
MadYugoslav earned 50 total points
ID: 6268384
char szText[] = "test?blah?123";char seps[]   = " ,\t\n";
char *token;
char *pszBuffer;

void GetLines( void )
{
   int i=0;
   pszBuffer = malloc (10 * 100);
   token = strtok( szText, "?" );
   while( token != NULL )
   {
      strcpy(pszBuffer[i*100], token
      i++;
      token = strtok( NULL, "?" );
   }
}

0
 
LVL 10

Expert Comment

by:makerp
ID: 6268551
here is a function i wrote a while back to strtok and return a array of pointers, it aint perfect and probably could be improved but it works

/* function to take a string and split it up into parts separted by
   seperator . returns a pointer to pointers !! */
char **splitText(const char *text, int *count, char* seperator)
{
     char **lines = NULL;
     char *ptr = NULL, *temp;
     int size = 0;
     /* set the count to one just in case */
     *count = 0;
     temp = (char*)malloc(strlen(text) + 1);
     if(!temp)
     {
          return NULL;
     }
     strcpy(temp,text);
     ptr = strtok(temp,seperator);
     while(ptr != NULL)
     {
          if(lines)
          {
                    size = _msize(lines);
          }
          lines = (char**)realloc(lines, size + sizeof(char*));
          if(lines)
          {
               lines[*count] = (char*)malloc(strlen(ptr) + 1);
               if(lines[*count])
               {
                    strcpy(lines[*count],ptr);
                    *count = *count + 1;
               }
          }
          ptr = strtok(NULL,seperator);
     }
     free(temp);
     return lines;
}
0
 
LVL 2

Expert Comment

by:MadYugoslav
ID: 6268569
I think that my comment also can be improved but work.
Is it ?
0
How to run any project with ease

Manage projects of all sizes how you want. Great for personal to-do lists, project milestones, team priorities and launch plans.
- Combine task lists, docs, spreadsheets, and chat in one
- View and edit from mobile/offline
- Cut down on emails

 
LVL 10

Expert Comment

by:makerp
ID: 6268726
to print out the values after calling simply

int count = 0;

char **retval = splitText(my_str,&count,"?")

for(int i=0;i<count;i++)
{
  printf("%s\n",retval[i])
}

then to free all of the values in the pointer array simply call this function passing the array and the count

i.e.

pm_free_ptr_2_ptr((void**)retval,count);

/* clean up a ** list of pointers */
void pm_free_ptr_2_ptr(void **ptr, int count)
{
     if(ptr)
     {    
          for(int i = 0;i < count;i++)
          {
               if(ptr[i])
               {
                    free(ptr[i]);
               }
          }
          free(ptr);
     }
}

to allocate each in a 100 bytes buffer simply replace

lines[*count] = (char*)malloc(strlen(ptr) + 1);
 with
lines[*count] = (char*)malloc(100);

although using just strcpy is dangerous now as your token may be greater then 100? so instead of

strcpy(lines[*count],ptr);
 use
strncpylines[*count],ptr,100);

paul

0
 
LVL 10

Expert Comment

by:makerp
ID: 6268730
strncpy(lines[*count],ptr,100);

whoops, missing (
0
 
LVL 1

Author Comment

by:Kitty__Kong
ID: 6269989
strcpy(pszBuffer[i*100], token)

is causing some warnings

D:\Programming\c_c++\strings\strings.c(19) : warning C4047: 'function' : 'char *' differs in levels of indirection from 'char '


D:\Programming\c_c++\strings\strings.c(19) : warning C4024: 'strcpy' : different types for formal and actual parameter 1
0
 

Expert Comment

by:wkmatt42
ID: 6270069
Try

strcpy(&pszBuffer[i*100], token)

or

strcpy(pszBuffer + i*100, token)
0

Featured Post

IT, Stop Being Called Into Every Meeting

Highfive is so simple that setting up every meeting room takes just minutes and every employee will be able to start or join a call from any room with ease. Never be called into a meeting just to get it started again. This is how video conferencing should work!

Join & Write a Comment

An Outlet in Cocoa is a persistent reference to a GUI control; it connects a property (a variable) to a control.  For example, it is common to create an Outlet for the text field GUI control and change the text that appears in this field via that Ou…
Windows programmers of the C/C++ variety, how many of you realise that since Window 9x Microsoft has been lying to you about what constitutes Unicode (http://en.wikipedia.org/wiki/Unicode)? They will have you believe that Unicode requires you to use…
The goal of this video is to provide viewers with basic examples to understand and use pointers in the C programming language.
The goal of this video is to provide viewers with basic examples to understand opening and reading files in the C programming language.

708 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

13 Experts available now in Live!

Get 1:1 Help Now