.\" Copyright 1993 David Metcalfe (david@prism.demon.co.uk)
.\"
.\" Permission is granted to make and distribute verbatim copies of this
.\" manual provided the copyright notice and this permission notice are
.\" preserved on all copies.
.\"
.\" Permission is granted to copy and distribute modified versions of this
.\" manual under the conditions for verbatim copying, provided that the
.\" entire resulting derived work is distributed under the terms of a
.\" permission notice identical to this one
.\" 
.\" Since the Linux kernel and libraries are constantly changing, this
.\" manual page may be incorrect or out-of-date.  The author(s) assume no
.\" responsibility for errors or omissions, or for damages resulting from
.\" the use of the information contained herein.  The author(s) may not
.\" have taken the same level of care in the production of this manual,
.\" which is licensed free of charge, as they might when working
.\" professionally.
.\" 
.\" Formatted or processed versions of this manual, if unaccompanied by
.\" the source, must acknowledge the copyright and authors of this work.
.\"
.\" References consulted:
.\"     Linux libc source code
.\"     Lewine's _POSIX Programmer's Guide_ (O'Reilly & Associates, 1991)
.\"     386BSD man pages
.\" Modified Sat Jul 24 19:48:17 1993 by Rik Faith (faith@cs.unc.edu)
.\"
.\" Traducido al castellano (con permiso) por:
.\" Sebastian Desimone (chipy@argenet.com.ar) (desimone@fasta.edu.ar)
.\" Translation fixed on Fri Apr 24 10:37:35 CEST 1998 by Gerardo
.\" Aburruzaga García <gerardo.aburruzaga@uca.es>
.\"
.TH DIFFTIME 3  "15 Enero 1995" "GNU" "Manual del Programador de Linux"
.SH NOMBRE
difftime \- calcula la diferencia entre dos tiempos
.SH SINOPSIS
.nf
.B #include <time.h>
.sp
.BI "double difftime(time_t " time1 ", time_t " time0 );
.fi
.SH DESCRIPCIÓN
La función \fBdifftime()\fP devuelve el número de segundos transcurridos
entre \fItime1\fP y \fItime0\fP, representado en coma flotante de doble precisión.  
Los dos tiempos se dan como tiempo de calendario, que representa el tiempo 
transcurrido desde la Época
(las 00:00:00 h del 1 de Enero de 1970, Tiempo Universal Coordinado (UTC)).
.SH "CONFORME A"
SVID 3, BSD 4.3, ISO 9899
.SH OBSERVACIONES
Esta función es requerida por el estándar ANSI C.
En un sistema POSIX, time_t es un tipo aritmético, y simplemente se
podría definir
.RS
.nf
#define difftime(t1,t0) (double)(t1 - t0)
.fi
.RE
cuando un posible desbordamiento por arriba de la resta no suponga una preocupación.
.SH "VÉASE TAMBIÉN"
.BR date "(1), " gettimeofday "(2), " time (2),
.BR ctime "(3), " gmtime "(3), " localtime (3)