Business Shell (BUSH) Guide
Author: Ken Burtch

Home Page | Introduction | Tutorials | Reference | Packages | Hacking

Packages
4.1 Using Packages
4.2 text_io (Console I/O)
4.3 text_io (File I/O)
4.4 sound
4.5 source_info
4.6 System
4.7 numerics
4.8 strings
4.9 command_line
4.10 lock_files
4.11 cgi
4.12 calendar
4.13 units
4.14 arrays
4.15 files
4.16 db (Database)
4.17 stats
4.18 pen
4.19 mysql
4.20 os
4.21 directory_operations
| This part of the guide contains detailed descriptions of the BUSH built-in packages. ### 4.10 lock_files Package A lock file is a file that, if it exists, indicates that a particular resource is in use. The lock_files package contains procedures to create and destroy lock files under any operating system. If a lock file cannot be locked, an error is reported. GCC Ada Equivalent: GNAT.Lock_Files lock_files.lock_file( [dir,] file, [, wait [, retries] ] )
create a lock file named file in optional directory dir. Retry up to retries (natural) times, waiting for wait (duration) seconds between retries. Default for wait/retries in 1.0 second and almost forever. Example: lock_files.lock_file( "test_lock.lck" ); Ada Equivalent: GNAT.Lock_Files.Lock_File Parameters:
dir | in | string | "." | the directory to place the lock file in
file | in | string | required | the name of the lock file
wait | in | duration | 1.0 | the number of seconds to wait between retries
retries | in | natural | largest natural | the maximum number of retries
If the file cannot be locked, BUSH reports an error. lock_files.unlock_file( [dir,] file )
delete the lock file name file in optional directory dir. Example: lock_files.unlock_file( "test_lock.lck" ); Ada Equivalent: GNAT.Lock_Files.Unlock_File Parameters:
dir | in | string | "." | the directory the lock file is in
file | in | string | required | the name of the lock file
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