time(1) — Reliant UNIX 5.44c4

time(1)                                                             time(1)

NAME
     time - time a command

SYNOPSIS
     time [-p] [--] prog [arg ...]

DESCRIPTION
     time can be used to measure the execution time of a program or a shell
     script. After the program or shell script is executed, time writes the
     following times to standard error: real, user, sys.

     -  real is the elapsed time during the invoked process and its child
        processes, i.e. the time between program call and program termina-
        tion.

     -  user is the time spent by the process or one of its child processes
        when executing user code. A process executes user code when it exe-
        cutes machine instructions from its own code segment.

     -  sys is the time spent by the process or one of its child processes
        when executing system code. A process executes system code when it
        executes machine instructions from system calls.

     Note:
        If time is called on a multiprocessor system, the sum of user and
        system time may be greater than real time. A figure of more than
        100% for the apparent CPU load is the result of child processes
        being split between a number of processors.

OPTIONS
     No option specified:
          The output has the format hh:mm:ss.zz, whereby hh stands for
          hours, mm for minutes, ss for seconds, and zz for hundredths of a
          second.

     -p   The time is output in seconds as a floating point number with at
          least one place after the decimal point.

     --   End of the list of options. Must be specified if prog begins with
          -.

     prog Name of the program (or shell script) to be timed.

     arg  Optional arguments that may be passed to prog exactly as if prog
          were called without time.










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time(1)                                                             time(1)

EXIT STATUS
     If command was called, time returns the exit status of the executed
     command command. Otherwise, time returns one of the following values:

     1-125   An error occurred in the time command.

     126     The specified command exists, but cannot be executed.

     127     The specified command cannot be found.

LOCALE
     The LCMESSAGES environment variable governs the language in which
     message texts are displayed. If LCMESSAGES is undefined or is defined
     as the null string, it defaults to the value of LANG. If LANG is like-
     wise undefined or null, the system acts as if it were not internation-
     alized.

     The LCALL environment variable governs the entire locale. LCALL
     takes precedence over all the other environment variables which affect
     internationalization.


































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time(1)                                                             time(1)

EXAMPLES
     Measure the execution time of the ls command. The standard output of
     ls is redirected to the file list.

     $ time ls -l >list
     real    0m0.21s
     user    0m0.06s
     sys     0m0.06s

SEE ALSO
     times(1), timex(1), xpg4sh(1), times(2).











































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