Chapter 31. System Interaction
- alarm exprâ
Schedules a
SIGALRM
signal to be delivered after expr seconds. If expr is zero, cancels a pending timer.- chdir [ expr ]
Changes the working directory. Uses
$ENV{HOME}
or$ENV{LOGNAME}
if expr is omitted.- chroot filenameâ
Changes the root directory for the process and any future children.
- die [ list ]
Prints the value of list to
STDERR
and exits with value$! || ($? >> 8) || 255.
list defaults toDied.
Inside an eval, the error message is stuffed into
$@,
and the eval is terminated returning undef ; this makes die the way to raise an exception.- exec [ program ] list
Executes the system command in list; does not return. program can be used to explictly designate the program to execute the command.
- exit [ expr ]
Exits immediately with the value of expr, which defaults to zero. Calls END routines and object destructors before exiting.
- fork
Does a fork syscall. Returns the process id of the child to the parent process (or undef on failure) and zero to the child process.
- getlogin
Returns the current login name as known by the system. If it returns false, use getpwuid.
- getpgrp [ pid ]
Returns the process group for process pid. If pid is zero, or omitted, uses the current process.
- getppid
Returns the process id of the parent process.
- getpriority which, who
Returns the current priority for a process, process group, or user. Use
getpriority 0,0
to designate the current process.- glob exprâ
Returns a list of filenames that match the C-shell pattern(s) in expr. Use ...
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