[PATCH] errno.3: add some comments on EAGAIN/EWOULDBLOCK and EDEADLK/EDEADLOCK

[PATCH] errno.3: add some comments on EAGAIN/EWOULDBLOCK and EDEADLK/EDEADLOCK

[Rasmus Villemoes]

Signed-off-by: Rasmus Villemoes <rv@rasmusvillemoes.dk>
---
 man3/errno.3 | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/man3/errno.3 b/man3/errno.3
index 6cbbafed5..794be7c7b 100644
--- a/man3/errno.3
+++ b/man3/errno.3
@@ -94,7 +94,7 @@ must have distinct values, with the exception of
 .B EAGAIN
 and
 .BR EWOULDBLOCK ,
-which may be the same.
+which may be the same. On Linux, these two always have the same value.
 .PP
 The error numbers that correspond to each symbolic name
 vary across UNIX systems,
@@ -240,8 +240,9 @@ Connection reset (POSIX.1-2001).
 Resource deadlock avoided (POSIX.1-2001).
 .TP
 .B EDEADLOCK
-Synonym for
+On most platforms, a synonym for
 .BR EDEADLK .
+On some (e.g. Linux mips, powerpc, sparc), it is a separate error code "File locking deadlock error".
 .TP
 .B EDESTADDRREQ
 Destination address required (POSIX.1-2001).
-- 
2.11.0

Re: [PATCH] errno.3: add some comments on EAGAIN/EWOULDBLOCK and EDEADLK/EDEADLOCK

[Michael Kerrisk (man-pages)]

Hello Rasmus,

On 8/29/19 12:06 PM, Rasmus Villemoes wrote:
> Signed-off-by: Rasmus Villemoes <rv@rasmusvillemoes.dk>
> ---
>  man3/errno.3 | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)

Thanks. I applied and tweaked a little.

Thanks,

Michael

> diff --git a/man3/errno.3 b/man3/errno.3
> index 6cbbafed5..794be7c7b 100644
> --- a/man3/errno.3
> +++ b/man3/errno.3
> @@ -94,7 +94,7 @@ must have distinct values, with the exception of
>  .B EAGAIN
>  and
>  .BR EWOULDBLOCK ,
> -which may be the same.
> +which may be the same. On Linux, these two always have the same value.
>  .PP
>  The error numbers that correspond to each symbolic name
>  vary across UNIX systems,
> @@ -240,8 +240,9 @@ Connection reset (POSIX.1-2001).
>  Resource deadlock avoided (POSIX.1-2001).
>  .TP
>  .B EDEADLOCK
> -Synonym for
> +On most platforms, a synonym for
>  .BR EDEADLK .
> +On some (e.g. Linux mips, powerpc, sparc), it is a separate error code "File locking deadlock error".
>  .TP
>  .B EDESTADDRREQ
>  Destination address required (POSIX.1-2001).
> 


-- 
Michael Kerrisk
Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/
Linux/UNIX System Programming Training: http://man7.org/training/