getting integers from unknown number of lines from a file.

[scubber]

hi, im new (as you're going to painfully aware of in a minute) to programming and was wondering if anyone could help with this little problem:

i am trying to read a number of values which are separated by newlines, and then manipulate each number until a number =<0 is observed.
is there a way i can use something like fgets() to read the line, then once the manipulation is over, print the result and for the process to be repeated with the number from the next line down in the file?
guessing this would mean id use a "while (integer in question >0), do manipulation and repeat" kinda loop. errr... yeah. the problem is i cant convert my crazy words into a language.

here is what i have so far:

do
{
puts("enter filename");
scanf("%s",name);
FILE*ft;//designates the title ft to the file
ft = fopen(name,"r");//opens the file
if( NULL !=ft)//if the file isnt NULL, then:
{
char filetemps[600];
fgets (filetemps , 600 , ft);//reads the first line only.
puts (filetemps);//just to check it was reading it.
{

else//if the file is NULL prints error statement
{
printf("\nCannot open, please try again %s\n", name);
}//ends else

printf("done\n");
return 2;
}while(name[0]!='z');//ends do

a sample input would be:
294
576
575
-1

thanks for any help you might give me!

[Ganon11]

First thing I see is that return statement right before you end your do...while loop. Since that's not in any brackets or anything, it's going to end the program without executing any additional times. In other words, the loop will be nullified. Also, you have your filename retrieval inside this loop - meaning you'll be opening a file every time the first number is greater than 0.

You should get the name of the file first, before the loop. Once you have the file opened, then you can use a loop to start reading values. Since fgets retrieves info as a string, you may wish to use fscanf so you can directly access the data as an integer.