newlib-cygwin/newlib/libc/reent/readr.c

64 lines
1.3 KiB
C
Raw Normal View History

2000-02-18 03:39:52 +08:00
/* Reentrant versions of read system call. */
#include <reent.h>
#include <unistd.h>
#include <_syslist.h>
/* Some targets provides their own versions of this functions. Those
targets should define REENTRANT_SYSCALLS_PROVIDED in TARGET_CFLAGS. */
#ifdef _REENT_ONLY
#ifndef REENTRANT_SYSCALLS_PROVIDED
#define REENTRANT_SYSCALLS_PROVIDED
#endif
#endif
#ifndef REENTRANT_SYSCALLS_PROVIDED
/* We use the errno variable used by the system dependent layer. */
#undef errno
extern int errno;
/*
FUNCTION
<<_read_r>>---Reentrant version of read
INDEX
_read_r
ANSI_SYNOPSIS
#include <reent.h>
_ssize_t _read_r(struct _reent *<[ptr]>,
int <[fd]>, void *<[buf]>, size_t <[cnt]>);
2000-02-18 03:39:52 +08:00
TRAD_SYNOPSIS
#include <reent.h>
_ssize_t _read_r(<[ptr]>, <[fd]>, <[buf]>, <[cnt]>)
2000-02-18 03:39:52 +08:00
struct _reent *<[ptr]>;
int <[fd]>;
char *<[buf]>;
size_t <[cnt]>;
DESCRIPTION
This is a reentrant version of <<read>>. It
takes a pointer to the global data block, which holds
<<errno>>.
*/
_ssize_t
2000-02-18 03:39:52 +08:00
_read_r (ptr, fd, buf, cnt)
struct _reent *ptr;
int fd;
_PTR buf;
size_t cnt;
{
_ssize_t ret;
2000-02-18 03:39:52 +08:00
errno = 0;
if ((ret = (_ssize_t)_read (fd, buf, cnt)) == -1 && errno != 0)
2000-02-18 03:39:52 +08:00
ptr->_errno = errno;
return ret;
}
#endif /* ! defined (REENTRANT_SYSCALLS_PROVIDED) */