32v 1m at

AT(1) UNIX Programmer's Manual AT(1)

NAME

    at - execute commands at a later time

SYNOPSIS

    at time [ day ] [ file ]

DESCRIPTION

    _A_t squirrels away a copy of the named _f_i_l_e (standard input
    default) to be used as input to _s_h(1) at a specified later
    time.  A _c_d(1) command to the current directory is inserted
    at the beginning, followed by assignments to all environment
    variables.  When the script is run, it uses the user and
    group ID of the creator of the copy file.

    The _t_i_m_e is 1 to 4 digits, with an optional following `A',
    `P', `N' or `M' for AM, PM, noon or midnight.  One and two
    digit numbers are taken to be hours, three and four digits
    to be hours and minutes.  If no letters follow the digits, a
    24 hour clock time is understood.

    The optional _d_a_y is either (1) a month name followed by a
    day number, or (2) a day of the week; if the word `week'
    follows invocation is moved seven days further off.  Names
    of months and days may be recognizably truncated.  Examples
    of legitimate commands are

         at 8am jan 24
         at 1530 fr week

    _A_t programs are executed by periodic execution of the com-
    mand /_u_s_r/_l_i_b/_a_t_r_u_n from _c_r_o_n(1).  The granularity of _a_t
    depends upon how often _a_t_r_u_n is executed.

    Standard output or error output is lost unless redirected.

FILES

    /usr/spool/at/yy.ddd.hhhh.uu
    activity to be performed at hour _h_h_h_h of year day _d_d_d of
    year _y_y.  _u_u is a unique number.
    /usr/spool/at/lasttimedone contains _h_h_h_h for last hour of
    activity.
    /usr/spool/at/past directory of activities now in progress
    /usr/lib/atrun program that executes activities that are due
    pwd(1)

SEE ALSO

    calendar(1), cron(1)

DIAGNOSTICS

    Complains about various syntax errors and times out of
    range.

BUGS

    Due to the granularity of the execution of /_u_s_r/_l_i_b/_a_t_r_u_n,
    there may be bugs in scheduling things almost exactly 24
    hours into the future.