Is read(2) part of the C89 specification?

I'm somewhat new to C. I am wondering, is the

read(2)

function part of the C89 specification, or just the POSIX one? I ask since I was trying to figure out the return type for

read

, and the man pages in places such as here say it's

ssize_t

. However,

ssize_t

is only required in POSIX, not regular C according to this question. This MSDN page seems to confirm my suspicions, since it says

This POSIX function is deprecated. Use the ISO C++ conformant _read instead.

I got a hold of the draft of the C89 standard, and there is no mention of read in the table of contents. There is, however, a mention of

fread

: http://port70.net/~nsz/c/c89/c89-draft.html#4.9.8.1

So then is it better to use e.g.

fread(buf, 1, sizeof(buf), stdin)

rather than

read(STDIN_FILENO, buf, sizeof(buf))

for reading from standard input?

edit: Sorry for the confusion. I did not quote MSDN to suggest that

read

was deprecated, merely to show that it is indeed a part of the POSIX standard (it mentions "POSIX function") as opposed to the C standard.

rici

Answer

read() is not and never has been standard C, so if you want to write portable code which reads from files, don't use it; use fread().

On the other hand, there may be things you want to do on a Posix system which are not portable, such as use pipes and sockets. In that case, go ahead and use the Posix interfaces.

Source (Stackoverflow)

http://stackoverflow.com/questions/39301636/is-read2-part-of-the-c89-specification

Is read(2) part of the C89 specification?

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