diff options
Diffstat (limited to 'Doc/Zsh/mod_system.yo')
| -rw-r--r-- | Doc/Zsh/mod_system.yo | 24 |
1 files changed, 17 insertions, 7 deletions
diff --git a/Doc/Zsh/mod_system.yo b/Doc/Zsh/mod_system.yo index 6292af071..884c3e753 100644 --- a/Doc/Zsh/mod_system.yo +++ b/Doc/Zsh/mod_system.yo @@ -62,6 +62,9 @@ suppress updating of the file atime item(tt(nofollow))( fail if var(file) is a symbolic link ) +item(tt(nonblock))( +the file is opened in nonblocking mode +) item(tt(sync))( request that writes wait until data has been physically written ) @@ -166,7 +169,7 @@ 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 +199,16 @@ 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) is limited to 2^30-1 seconds (about 34 years), and +var(interval) to 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; @@ -256,9 +266,9 @@ tt($$), which returns the process ID of the main shell process. ) item(tt(ppid))( vindex(ppid, sysparams) -Returns the process ID of the parent of the current process, even in -subshells. Compare tt($PPID), which returns the process ID of the parent -of the main shell process. +Returns the current process ID of the parent of the current process, even +in subshells. Compare tt($PPID), which returns the process ID of the +initial parent of the main shell process. ) item(tt(procsubstpid))( Returns the process ID of the last process started for process |