PROTO(4)PROTO(4)NAMEproto - prototype job file for at
SYNOPSIS
/usr/lib/cron/.proto
/usr/lib/cron/.proto.queue
DESCRIPTION
When a job is submitted to at(1) or batch(1), the job is constructed as a
shell script. First, a prologue is constructed, consisting of:
o A header whether the job is an at job or a batch job (actually, at
jobs submitted to all queues other than queue a, not just to the batch
queue b, are listed as batch jobs); the header will be
: at job
for an at job, and
: batch job
for a batch job.
o A set of Bourne shell commands to make the environment (see
environ(5)) for the at job the same as the current environment;
o A command to run the user's shell (as specified by the SHELL
environment variable) with the rest of the job file as input.
At then reads a "prototype file," and constructs the rest of the job file
from it.
Text from the prototype file is copied to the job file, except for
special "variables" that are replaced by other text:
$d is replaced by the current working directory
$l is replaced by the current file size limit (see ulimit(2))
$m is replaced by the current umask (see umask(2))
$t is replaced by the time at which the job should be run,
expressed as seconds since January 1, 1970, 00:00 Greenwich
Mean Time, preceded by a colon
$< is replaced by text read by at from the standard input (that
is, the commands provided to at to be run in the job)
If the job is submitted in queue queue, at uses the file
/usr/lib/cron/.proto.queue as the prototype file if it exists, otherwise
it will use the file /usr/lib/cron/.proto.
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PROTO(4)PROTO(4)EXAMPLES
The standard .proto file supplied is:
#ident "@(#)adm:.proto 1.2"
cd $d
ulimit $l
umask $m
$<
which causes commands to change the current directory in the job to the
current directory at the time at was run, to change the file size limit
in the job to the file size limit at the time at was run, and to change
the umask in the job to the umask at the time at was run, to be inserted
before the commands in the job.
FILES
/usr/lib/cron/.proto
/usr/lib/cron/.proto.queue
SEE ALSOat(1)
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