mirrors/zsh
1
0
Fork 0
mirror of git://git.code.sf.net/p/zsh/code synced 2025-10-23 16:40:24 +02:00
Code Releases Activity

45708: zsh/system: Enable sub-second timeout in zsystem flock

Browse source
This commit is contained in:
Cedric Ware 2020-04-20 12:10:01 -05:00 • committed by dana
parent f179dbf72a
commit 25c9b61a66
6 changed files with 302 additions and 9 deletions
Download patch file Download diff file Expand all files Collapse all files

16
Doc/Zsh/mod_system.yo
View file

@ -166,7 +166,7 @@ to the command, or 2 for an error on the write; no error message is
printed in the last case, but the parameter tt(ERRNO) will reflect
the error that occurred.
)
xitem(tt(zsystem flock) [ tt(-t) var(timeout) ] [ tt(-f) var(var) ] [tt(-er)] var(file))
xitem(tt(zsystem flock) [ tt(-t) var(timeout) ] [ tt(-i) var(interval) ] [ tt(-f) var(var) ] [tt(-er)] var(file))
item(tt(zsystem flock -u) var(fd_expr))(
The builtin tt(zsystem)'s subcommand tt(flock) performs advisory file
locking (via the manref(fcntl)(2) system call) over the entire contents
@ -196,9 +196,17 @@ a safety check that the file descriptor is in use for file locking.
By default the shell waits indefinitely for the lock to succeed.
The option tt(-t) var(timeout) specifies a timeout for the lock in
seconds; currently this must be an integer. The shell will attempt
to lock the file once a second during this period. If the attempt
times out, status 2 is returned.
seconds; fractional seconds are allowed. During this period, the
shell will attempt to lock the file every var(interval) seconds
if the tt(-i) var(interval) option is given, otherwise once a second.
(This var(interval) is shortened before the last attempt if needed,
so that the shell waits only until the var(timeout) and not longer.)
If the attempt times out, status 2 is returned.
(Note: var(timeout) must be less than
ifzman(2^30-1)ifnzman(2NOTRANS(@sup{30})-1) seconds (about 34 years),
and var(interval) must be less than 0.999 * LONG_MAX microseconds
(only about 35 minutes on 32-bit systems).)
If the option tt(-e) is given, the file descriptor for the lock is
preserved when the shell uses tt(exec) to start a new process;