time [–p] command-line
tcsh shell: time [command]
time runs the command given as its argument and produces a breakdown of total time to run (real), total time spent in the user program (user), and total time spent in system processor overhead (sys).
Times given are statistical, based on where execution is at a clock tick. Output is written to standard error.
time is a built-in shell command.
In the tcsh shell, time executes command (which must be a simple command, not an alias, a pipeline, a command list, or a parenthesized command list) and prints a time summary as described under the tcsh time variable (see tcsh — Invoke a C shell). If necessary, an extra shell is created to print the time statistic when the command completes. Without command, time prints a time summary for the current shell and its children.
See Localization for more information.
POSIX.2 User Portability Extension, X/Open Portability Guide, UNIX systems.
sh, tcsh