U:RDoc::AnyMethod[iI"
flock:ETI"File#flock;TF: publico:RDoc::Markup::Document: @parts[
o: RDoc::Markup::Paragraph; [
I"ELocks or unlocks a file according to locking_constant (a ;TI"or of the values in the table below). ;TI"AReturns false if File::LOCK_NB is ;TI"Cspecified and the operation would otherwise have blocked. Not ;TI" available on all platforms.;To: RDoc::Markup::BlankLine o;
; [I"'Locking constants (in class File):;T@o:RDoc::Markup::Verbatim; [I">LOCK_EX | Exclusive lock. Only one process may hold an
;TI"< | exclusive lock for a given file at a time.
;TI"A----------+------------------------------------------------
;TI";LOCK_NB | Don't block when locking. May be combined
;TI"; | with other lock options using logical or.
;TI"A----------+------------------------------------------------
;TI"ALOCK_SH | Shared lock. Multiple processes may each hold a
;TI"@ | shared lock for a given file at the same time.
;TI"A----------+------------------------------------------------
;TI"LOCK_UN | Unlock.
;T: @format0o;
; [I"
Example:;T@o; ; [I")# update a counter using write lock
;TI"@# don't use "w" because it truncates the file before lock.
;TI"=File.open("counter", File::RDWR|File::CREAT, 0644) {|f|
;TI" f.flock(File::LOCK_EX)
;TI" value = f.read.to_i + 1
;TI" f.rewind
;TI" f.write("#{value}\n")
;TI" f.flush
;TI" f.truncate(f.pos)
;TI"}
;TI"
;TI"(# read the counter using read lock
;TI"$File.open("counter", "r") {|f|
;TI" f.flock(File::LOCK_SH)
;TI" p f.read
;TI"};T;
0:
@fileI" file.c;T:0@omit_headings_from_table_of_contents_below0I"0file.flock(locking_constant) -> 0 or false
;T0[ I" (p1);T@7FI" File;TcRDoc::NormalClass00