is 0 bytes read EOF ?

abachus has asked for the wisdom of the Perl Monks concerning the following question:

Hi all,

I have a quick question :
When reading from a handle, with say sysread(), if the call returns 0 bytes read, is this a reliable indication that the handle pointer (for want of better terminology) is at EOF ?

many thanks,

Isaac.

Comment on is 0 bytes read EOF ?

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Re: is 0 bytes read EOF ? by blue_cowdawg (Monsignor) on Sep 11, 2006 at 21:26 UTC
When reading from a handle, with say sysread(), if the call returns 0 bytes read, is this a reliable indication that the handle pointer (for want of better terminology) is at EOF ? This from `perldoc -f sysread` "There is no syseof() function, which is ok, since eof() doesn’t work very well on device files (like ttys) anyway. Use sys- read() and check for a return value for 0 to decide whether you’re done. " Does this answer the question? This by the way must be my "evil" post because it is the 666^th post! BWAHAHAHAHAAHAHAHA!!! Peter L. Berghold -- Unix Professional Peter -at- Berghold -dot- Net; AOL IM redcowdawg Yahoo IM: blue_cowdawg	[reply] [d/l]
Re: is 0 bytes read EOF ? by friedo (Prior) on Sep 11, 2006 at 21:28 UTC
As the docs indicate, a return of zero means EOF, and a return of undef means error.	[reply]
Re: is 0 bytes read EOF ? by GrandFather (Saint) on Sep 11, 2006 at 21:30 UTC
The documentation for sysread says that it returns 0 on EOF. DWIM is Perl's answer to Gödel	[reply]
Re^2: is 0 bytes read EOF ? by abachus (Monk) on Sep 12, 2006 at 13:19 UTC
Thanks monks, I just wanted to be sure, i'm putting together a bit of code with select(), i will post here when help is needed.	[reply]