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Old 11-13-2006, 08:08 PM   #1
ygloo
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pipe output loaded into an array (c)


data coming from a pipe is directory list... ( command "ls" ),
i try to put every filename into an array...

Code:
# include <stdio.h>

int main()
{
   FILE *ls_pipe;
   char delim[] = " ";   //   this whitespace??
   char *split_input = NULL;
      
   ls_pipe = popen ("ls", "r");

   split_input = strtok (ls_pipe, delim);
   	while (split_input != NULL)
	   { 
	       printf("split_input is \"%s\"\n", split_input);
	       split_input = strtok(NULL, delim);
	   }

   pclose (ls_pipe);
   return 0;   
}
it compiles with this message:color.c:
In function `main':
color.c:10: warning: assignment makes pointer from integer without a cast
color.c:14: warning: assignment makes pointer from integer without a cast

Last edited by ygloo; 11-17-2006 at 07:30 AM.
 
Old 11-13-2006, 09:10 PM   #2
nadroj
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the signature of strtok is: char * strtok ( const char * string, const char * delimiters );
but when you first call it you call it with string (ls_pipe) being a FILE*, is this your problem?

also are you using this without includeing string.h? are you excluding any code in your post?
 
Old 11-14-2006, 11:38 AM   #3
ygloo
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this is all the code...
i saw how to use strok here:
http://www.cppreference.com/stdstring/strtok.html
 
Old 11-14-2006, 12:00 PM   #4
nadroj
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strtok is in the string.h file, i cant compile this because it gives errors saying it doesnt know what strtok is. i dont see how you dont get these errors?! do #include<string.h> and see if anything changes..

again, for the first time when you use strtok you call it as such:
(FILE*, char*);
but it wants:
(const char* string, const char* delimiters);

can you upload and send a link this file (color.c)?
 
Old 11-14-2006, 12:15 PM   #5
ygloo
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i posted all file code above
after including "string.h" there is this message:
color.c:11: warning: passing arg 1 of `strtok' from incompatible pointer type
 
Old 11-14-2006, 12:17 PM   #6
nadroj
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its referring to what i said in my previous post, you cant pass ls_pipe/FILE*. they have to be char*'s
 
Old 11-14-2006, 04:43 PM   #7
ygloo
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changed "FILE *ls_pipe;"
to "char *ls_pipe;"..
not working...
 
Old 11-14-2006, 06:10 PM   #8
nadroj
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whats not working now? same error? different error? if you want help you need to be specific

i dont have access to a linux machine so i cant test this code
 
Old 11-15-2006, 11:59 AM   #9
ygloo
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compile message is:
color.c: In function `main':
color.c:11: warning: passing arg 1 of `strtok' from incompatible pointer type
 
Old 11-15-2006, 12:10 PM   #10
nadroj
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can you make another char* but make it const and set it to the one your passing? pass this new const char* instead.. i dont see why it wouldnt work.

also if you changed your FILE* to char* are you still doing the popen call? are you not getting errors there?
 
Old 11-15-2006, 12:44 PM   #11
orgcandman
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You need to reread your man pages.

popen gives you a file pointer. But that doesn't contain any actual data that you care about. You have to read from the file, and then pass that data to strtok.
 
Old 11-15-2006, 01:05 PM   #12
ygloo
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i try to pass stream from "popen" directly to "strtok"
 
Old 11-15-2006, 01:30 PM   #13
nadroj
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you cant give strtok a (file) stream. if this isnt what you mean post code to go with it as its usually easier to understand
 
Old 11-15-2006, 01:32 PM   #14
nadroj
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check out the example here: http://www.opengroup.org/onlinepubs/...ons/popen.html
Quote:
The following example demonstrates the use of popen() and pclose() to execute the command ls * in order to obtain a list of files in the current directory:
 
Old 11-15-2006, 11:04 PM   #15
bruce_goose
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Hi Ygloo,

you may have your reasons for doing this with the popen command - but have you come across the opendir/readdir/closedir commands ? I feel they give you much more control than token seeking does.

Cheers,

Bruce.
 
  


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