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All advertising materials mentioning features or use of this software .\" must display the following acknowledgement: .\" This product includes software developed by the University of .\" California, Berkeley and its contributors. .\" 4. Neither the name of the University nor the names of its contributors .\" may be used to endorse or promote products derived from this software .\" without specific prior written permission. .\" .\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE .\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF .\" SUCH DAMAGE. .\" %%%LICENSE_END .\" .\" @(#)fread.3 6.6 (Berkeley) 6/29/91 .\" .\" Converted for Linux, Mon Nov 29 15:37:33 1993, faith@cs.unc.edu .\" Sun Feb 19 21:26:54 1995 by faith, return values .\" Modified Thu Apr 20 20:43:53 1995 by Jim Van Zandt .\" Modified Fri May 17 10:21:51 1996 by Martin Schulze .\" .\"******************************************************************* .\" .\" This file was generated with po4a. Translate the source file. .\" .\"******************************************************************* .TH FREAD 3 "13 Agosto 2020" GNU "Manual del Programador de Linux" .SH NOMBRE fread, fwrite \- entrada/salida binaria de flujos de datos .SH SINOPSIS .nf \fB#include \fP .PP \fBsize_t fread(void *\fP\fIptr\fP\fB, size_t \fP\fItam\fP\fB, size_t \fP\fInmiemb\fP\fB, FILE *\fP\fIflujo\fP\fB);\fP .PP \fBsize_t fwrite(const void *\fP\fIptr\fP\fB, size_t \fP\fItam\fP\fB, size_t \fP\fInmiemb\fP\fB,\fP \fB FILE *\fP\fIflujo\fP\fB);\fP .fi .SH DESCRIPCIÓN La función \fBfread\fP() lee \fInmiemb\fP elementos de datos, cada uno de \fItam\fP bytes de largo, del flujo de datos apuntado por \fIflujo\fP, almacenándolos en el sitio apuntado por \fIptr\fP. .PP La función \fBfwrite\fP() escribe \fInmiemb\fP elementos de datos, cada uno de \fItam\fP bytes de largo, al flujo de datos apuntado por \fIflujo\fP, obteniéndolos del sitio apuntado por \fIptr\fP. .PP Para las versiones no\-bloqueantes, véase \fBunlocked_stdio\fP(3). .SH "VALOR DEVUELTO" On success, \fBfread\fP() and \fBfwrite\fP() return the number of items read or written. This number equals the number of bytes transferred only when \fIsize\fP is 1. If an error occurs, or the end of the file is reached, the return value is a short item count (or zero). .PP The file position indicator for the stream is advanced by the number of bytes successfully read or written. .PP \fBfread\fP() no distingue entre fin\-de\-fichero y error, así que quien llame a esta función debe emplear \fBfeof\fP(3) y \fBferror\fP(3) para determinar qué ha ocurrido. .SH ATRIBUTOS Para obtener una explicación de los términos usados en esta sección, véase \fBattributes\fP(7). .TS allbox; lbw17 lb lb l l l. Interfaz Atributo Valor T{ \fBfread\fP(), \fBfwrite\fP() T} Seguridad del hilo Multi\-hilo seguro .TE .SH "CONFORME A" POSIX.1\-2001, POSIX.1\-2008, C89. .SH EJEMPLOS The program below demonstrates the use of \fBfread\fP() by parsing /bin/sh ELF executable in binary mode and printing its magic and class: .PP .in +4n .EX $ \fB./a.out\fP ELF magic: 0x7f454c46 Class: 0x02 .EE .in .SS "Código fuente" \& .EX #include #include #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0])) int main(void) { FILE *fp = fopen("/bin/sh", "rb"); if (!fp) { perror("fopen"); return EXIT_FAILURE; } unsigned char buffer[4]; size_t ret = fread(buffer, ARRAY_SIZE(buffer), sizeof(*buffer), fp); if (ret != sizeof(*buffer)) { fprintf(stderr, "fread() failed: %zu\en", ret); exit(EXIT_FAILURE); } printf("ELF magic: %#04x%02x%02x%02x\en", buffer[0], buffer[1], buffer[2], buffer[3]); ret = fread(buffer, 1, 1, fp); if (ret != 1) { fprintf(stderr, "fread() failed: %zu\en", ret); exit(EXIT_FAILURE); } printf("Class: %#04x\en", buffer[0]); fclose(fp); exit(EXIT_SUCCESS); } .EE .SH "VÉASE TAMBIÉN" \fBread\fP(2), \fBwrite\fP(2), \fBfeof\fP(3), \fBferror\fP(3), \fBunlocked_stdio\fP(3) .SH COLOFÓN Esta página es parte de la versión 5.10 del proyecto Linux \fIman\-pages\fP. Puede encontrar una descripción del proyecto, información sobre cómo informar errores y la última versión de esta página en \%https://www.kernel.org/doc/man\-pages/. .PP .SH TRADUCCIÓN La traducción al español de esta página del manual fue creada por Gerardo Aburruzaga García . .PP Esta traducción es documentación libre; lea la .UR https://www.gnu.org/licenses/gpl-3.0.html GNU General Public License Version 3 .UE o posterior con respecto a las condiciones de copyright. No existe NINGUNA RESPONSABILIDAD. .PP Si encuentra algún error en la traducción de esta página del manual, envíe un correo electrónico a .MT debian-l10n-spanish@lists.debian.org .ME .