diff options
Diffstat (limited to 'usr/src/man/man3proc/proc_initstdio.3proc')
| -rw-r--r-- | usr/src/man/man3proc/proc_initstdio.3proc | 31 |
1 files changed, 17 insertions, 14 deletions
diff --git a/usr/src/man/man3proc/proc_initstdio.3proc b/usr/src/man/man3proc/proc_initstdio.3proc index 315f717f81..5576c33dfa 100644 --- a/usr/src/man/man3proc/proc_initstdio.3proc +++ b/usr/src/man/man3proc/proc_initstdio.3proc @@ -41,17 +41,19 @@ The and .Fn proc_finistdio functions are utilities provided to aid with the possibility of deadlock -while doing I/O operations. If a process is trying to do I/O, but -holding the process handle that would consume that I/O, then eventually -the program holding the process handle will block as none of its I/O has -been drained. However, because it is holding a process handle to that -process, it will never be drained. +while doing I/O operations. +If a process is trying to do I/O, but holding the process handle that would +consume that I/O, then eventually the program holding the process handle will +block as none of its I/O has been drained. +However, because it is holding a process handle to that process, it will never +be drained. .Pp Consider, for example, the following invocation: .Li pfiles `pgrep xterm` -where the command was launched from a shell on an xterm. Because the -xterm is stopped, it will not be able to write out any of the standard -out that gets passed to it, leading to a deadlock. The +where the command was launched from a shell on an xterm. +Because the xterm is stopped, it will not be able to write out any of the +standard out that gets passed to it, leading to a deadlock. +The .Li pfiles program cannot release the .Li xterm @@ -60,9 +62,9 @@ due to the same hold. .Pp To address this, these functions duplicate the standard output and standard error of the process to temporary files and then flushes it out -to the original file descriptors and streams later. When finished, the -original file descriptors are restored as standard out and standard -error. +to the original file descriptors and streams later. +When finished, the original file descriptors are restored as standard out and +standard error. .Pp The .Fn proc_initstdio @@ -72,9 +74,10 @@ descriptors and retains the originals. The .Fn proc_flushstdio functions flushes all of the cached data from the temporary standard out -and standard error back to the underlying ones. This function should -only be called after all process handles have been released. For -example, if iterating on multiple processes, calling this after handling +and standard error back to the underlying ones. +This function should only be called after all process handles have been +released. +For example, if iterating on multiple processes, calling this after handling each one is safe. .Pp The |