Reading file line by line

[uber0ne]

Ok here what i want to do. I have a file named myfile.txt i want to pick a random number and have it read that line of the file.
EX.
hhhhh
jjjjjjjj
kkkkk
lllllllllll
yyyyy
tttttttt
and i want to pull out line 4 and store it in a variable so that
variable == lllllllllll
If this would be easier with an ini then please tell me.

[groepaz]

checkout fscanf, that should do the trick

[uber0ne]

i want to be able to tell the program line number 4 and it goes to line number 4 and pulls out the file or and number

[groepaz]

i dont think there are ready made functions that do exactly this...so you have to parse the file yourself. in most cases you might want to keep it buffered in ram anyway.

[uber0ne]

yea but how would i do that....

[Drakonite]

Learning C would be a good start.

[sg57]

Just as i had said and psoted on psp-programming.com...

Code: Select all

#include <stdio.h> 
// what line to go to&#58; 5 as example
#define GotoLine 5

// do not touch below
#define lineNumber 0

int main&#40;&#41; &#123; 
            
           char string&#91;1000&#93;; 
           int z; 
           FILE * pFile; 
  
           long lSize;  
           char * buffer;

           pFile = fopen &#40; "myfile.txt" , "rb"&#41;;  
            
           printf&#40;"File Opened Successuflly\n"&#41;; 
            
           fseek &#40;pFile , 0 , SEEK_END&#41;; 
  
           lSize = ftell &#40;pFile&#41;; 
  
           rewind &#40;pFile&#41;; 
  
           buffer = &#40;char*&#41; malloc &#40;lSize&#41;; 
            
           for &#40; z=lineNumber; z<GotoLine; z++ &#41; &#123; 
                  
           fgets&#40;buffer, lSize, pFile&#41;; 
           &#125; 

           printf&#40;"%s", buffer&#41;; 
            
           getch&#40;&#41;; 
return 0; 
&#125; 

Complied and tested WORKING via Dev-C++, if you wish to use this on the PSP, change getch(); to the sceKIernelSleepThread(); or delay, or whatever... Also, as you cna tell, the line number being read is fed into the buffer named 'buffer' so...

oh and to get a random line number from the file, then do this, since at psp-rpogramming you asked for random, AKA doing your ENTIRE code for you :(

Code: Select all

#include <stdio.h> 

#define GotoLine rand&#40;&#41;%100 

int main&#40;&#41; &#123; 
            
           char string&#91;1000&#93;; 
           int lineNumber = 0, z; 
           FILE * pFile; 
  
           long lSize;  
           char * buffer; 

           srand&#40;time&#40;&#41;&#41;; 

           pFile = fopen &#40; "myfile.txt" , "rb"&#41;;  
            
           printf&#40;"File Opened Successuflly\n"&#41;; 
            
           fseek &#40;pFile , 0 , SEEK_END&#41;; 
  
           lSize = ftell &#40;pFile&#41;; 
  
           rewind &#40;pFile&#41;; 
  
           buffer = &#40;char*&#41; malloc &#40;lSize&#41;; 
            
           for &#40; z=lineNumber; z<GotoLine; z++ &#41; &#123; 
                  
           fgets&#40;buffer, lSize, pFile&#41;; 
           &#125; 

           printf&#40;"%s", buffer&#41;; 
            
            
           getch&#40;&#41;; 
return 0; 
&#125; 

[boomint]

You may also want inform him that GotoLine definition assumes there are 100 lines in the file...

Code: Select all

#define GotoLine rand()%100 

And leave populating this with the actual number of lines in the file as an exercise for the reader ;)

[sg57]

well at psp-programming.com he had asked for something that will read a file line by line, when having like 5 lines in it, so i just assumed 100 for guessing. And theres a way to first get the number of lines in a file then have it done automaticaly... Use a loop,

while ( gets(file) 1= '\0') { puts(file); LineCount++; }