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分享open和fopen的区别？
请问各位高人，我想把open函数替换为fopen，怎么替换呢？我试了一个小程序，open函数返回值怎么都是3？而同样的用fopen，返回值是一个地址，我怎么能在不改变整个程序的前提下，用fopen代替open呢？
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swteetlove 2006-10-25
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学习中！！！！！！！
踏岸寻柳 2006-10-20
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open返回的是一个文件描述符，想想socket编程里面的句柄，也是一个文件描述符。
踏岸寻柳 2006-10-20
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前者属于低级IO，后者是高级IO。
前者返回一个文件描述符，后者返回一个文件指针。
前者无缓冲，后者有缓冲。
前者与 read, write 等配合使用， 后者与 fread, fwrite等配合使用。
后者是在前者的基础上扩充而来的，在大多数情况下，用后者。
这个回答基本上已经很完备了！
前者返回一个文件描述符，后者返回一个文件指针。
前者无缓冲，后者有缓冲。
前者与 read, write 等配合使用， 后者与 fread, fwrite等配合使用。
后者是在前者的基础上扩充而来的，在大多数情况下，用后者。
这个回答基本上已经很完备了！
flyinic 2006-10-20
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我现在是在arm下面的程序，不支持linux C,只能用fopen，但是源程序中的open用的地方有很多，郁闷！
davecom 2006-10-20
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佩服沙发！！
第2中麻烦讲解一下
第2中麻烦讲解一下
lockhall 2006-10-20
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都是大牛啊!:)
飞哥 2006-10-20
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一个是句柄，一个是描述符
差不多了～～～
没啥意思，卜研究了
闪人～
放假楼·
差不多了～～～
没啥意思，卜研究了
闪人～
放假楼·
ctu_85 2006-10-19
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前者属于低级IO，后者是高级IO。
前者返回一个文件描述符，后者返回一个文件指针。
前者无缓冲，后者有缓冲。
前者与 read, write 等配合使用， 后者与 fread, fwrite等配合使用。
后者是在前者的基础上扩充而来的，在大多数情况下，用后者。
前者返回一个文件描述符，后者返回一个文件指针。
前者无缓冲，后者有缓冲。
前者与 read, write 等配合使用， 后者与 fread, fwrite等配合使用。
后者是在前者的基础上扩充而来的，在大多数情况下，用后者。
pcboyxhy 2006-10-19
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Some of these optional flags can be altered using fcntl() after the
file has been opened.
The argument mode specifies the permissions to use in case a new file
is created. It is modified by the process’s umask in the usual way: the
permissions of the created file are (mode & ~umask). Note that this
mode only applies to future accesses of the newly created file; the
open() call that creates a read-only file may well return a read/write
file descriptor.
The following symbolic constants are provided for mode:
S_IRWXU
00700 user (file owner) has read, write and execute permission
S_IRUSR (S_IREAD)
00400 user has read permission
S_IWUSR (S_IWRITE)
00200 user has write permission
S_IXUSR (S_IEXEC)
00100 user has execute permission
S_IRWXG
00070 group has read, write and execute permission
S_IRGRP
00040 group has read permission
S_IWGRP
00020 group has write permission
S_IXGRP
00010 group has execute permission
S_IRWXO
00007 others have read, write and execute permission
S_IROTH
00004 others have read permission
S_IWOTH
00002 others have write permission
S_IXOTH
00001 others have execute permission
mode must be specified when O_CREAT is in the flags, and is ignored
otherwise.
creat() is equivalent to open() with flags equal to
O_CREAT|O_WRONLY|O_TRUNC.
RETURN VALUE
open() and creat() return the new file descriptor, or -1 if an error
occurred (in which case, errno is set appropriately). Note that open()
can open device special files, but creat() cannot create them; use
mknod(2) instead.
On NFS file systems with UID mapping enabled, open() may return a file
descriptor but e.g. read(2) requests are denied with EACCES. This is
because the client performs open() by checking the permissions, but UID
mapping is performed by the server upon read and write requests.
If the file is newly created, its st_atime, st_ctime, st_mtime fields
(respectively, time of last access, time of last status change, and
time of last modification; see stat(2)) are set to the current time,
and so are the st_ctime and st_mtime fields of the parent directory.
Otherwise, if the file is modified because of the O_TRUNC flag, its
st_ctime and st_mtime fields are set to the current time.
ERRORS
EACCES The requested access to the file is not allowed, or search per‐
mission is denied for one of the directories in the path prefix
of pathname, or the file did not exist yet and write access to
the parent directory is not allowed. (See also path_resolu‐
tion(2).)
EEXIST pathname already exists and O_CREAT and O_EXCL were used.
EFAULT pathname points outside your accessible address space.
EISDIR pathname refers to a directory and the access requested involved
writing (that is, O_WRONLY or O_RDWR is set).
ELOOP Too many symbolic links were encountered in resolving pathname,
or O_NOFOLLOW was specified but pathname was a symbolic link.
EMFILE The process already has the maximum number of files open.
ENAMETOOLONG
pathname was too long.
ENFILE The system limit on the total number of open files has been
reached.
ENODEV pathname refers to a device special file and no corresponding
device exists. (This is a Linux kernel bug; in this situation
ENXIO must be returned.)
ENOENT O_CREAT is not set and the named file does not exist. Or, a
directory component in pathname does not exist or is a dangling
symbolic link.
ENOMEM Insufficient kernel memory was available.
ENOSPC pathname was to be created but the device containing pathname
has no room for the new file.
ENOTDIR
A component used as a directory in pathname is not, in fact, a
directory, or O_DIRECTORY was specified and pathname was not a
directory.
ENXIO O_NONBLOCK | O_WRONLY is set, the named file is a FIFO and no
process has the file open for reading. Or, the file is a device
special file and no corresponding device exists.
EOVERFLOW
pathname refers to a regular file, too large to be opened; see
O_LARGEFILE above.
EPERM The O_NOATIME flag was specified, but the effective user ID of
the caller did not match the owner of the file and the caller
was not privileged (CAP_FOWNER).
EROFS pathname refers to a file on a read-only filesystem and write
access was requested.
ETXTBSY
pathname refers to an executable image which is currently being
executed and write access was requested.
EWOULDBLOCK
The O_NONBLOCK flag was specified, and an incompatible lease was
held on the file (see fcntl(2)).
NOTE
Under Linux, the O_NONBLOCK flag indicates that one wants to open but
does not necessarily have the intention to read or write. This is typ‐
ically used to open devices in order to get a file descriptor for use
with ioctl(2).
CONFORMING TO
SVr4, SVID, POSIX, X/OPEN, 4.3BSD. The O_NOATIME, O_NOFOLLOW, and
O_DIRECTORY flags are Linux-specific. One may have to define the
_GNU_SOURCE macro to get their definitions.
The (undefined) effect of O_RDONLY | O_TRUNC varies among implementa‐
tions. On many systems the file is actually truncated.
The O_DIRECT flag was introduced in SGI IRIX, where it has alignment
restrictions similar to those of Linux 2.4. IRIX has also a fcntl(2)
call to query appropriate alignments, and sizes. FreeBSD 4.x intro‐
duced a flag of same name, but without alignment restrictions. Support
was added under Linux in kernel version 2.4.10. Older Linux kernels
simply ignore this flag. One may have to define the _GNU_SOURCE macro
was added under Linux in kernel version 2.4.10. Older Linux kernels
simply ignore this flag. One may have to define the _GNU_SOURCE macro
to get its definition.
BUGS
"The thing that has always disturbed me about O_DIRECT is that the
whole interface is just stupid, and was probably designed by a deranged
monkey on some serious mind-controlling substances." — Linus
RESTRICTIONS
There are many infelicities in the protocol underlying NFS, affecting
amongst others O_SYNC and O_NDELAY.
POSIX provides for three different variants of synchronised I/O, corre‐
sponding to the flags O_SYNC, O_DSYNC and O_RSYNC. Currently (2.1.130)
these are all synonymous under Linux.
SEE ALSO
close(2), dup(2), fcntl(2), link(2), lseek(2), mknod(2), mount(2),
mmap(2), path_resolution(2), read(2), socket(2), stat(2), umask(2),
unlink(2), write(2), fopen(3), fifo(4)
Linux 2.6.12 2005-06-22 OPEN(2)
file has been opened.
The argument mode specifies the permissions to use in case a new file
is created. It is modified by the process’s umask in the usual way: the
permissions of the created file are (mode & ~umask). Note that this
mode only applies to future accesses of the newly created file; the
open() call that creates a read-only file may well return a read/write
file descriptor.
The following symbolic constants are provided for mode:
S_IRWXU
00700 user (file owner) has read, write and execute permission
S_IRUSR (S_IREAD)
00400 user has read permission
S_IWUSR (S_IWRITE)
00200 user has write permission
S_IXUSR (S_IEXEC)
00100 user has execute permission
S_IRWXG
00070 group has read, write and execute permission
S_IRGRP
00040 group has read permission
S_IWGRP
00020 group has write permission
S_IXGRP
00010 group has execute permission
S_IRWXO
00007 others have read, write and execute permission
S_IROTH
00004 others have read permission
S_IWOTH
00002 others have write permission
S_IXOTH
00001 others have execute permission
mode must be specified when O_CREAT is in the flags, and is ignored
otherwise.
creat() is equivalent to open() with flags equal to
O_CREAT|O_WRONLY|O_TRUNC.
RETURN VALUE
open() and creat() return the new file descriptor, or -1 if an error
occurred (in which case, errno is set appropriately). Note that open()
can open device special files, but creat() cannot create them; use
mknod(2) instead.
On NFS file systems with UID mapping enabled, open() may return a file
descriptor but e.g. read(2) requests are denied with EACCES. This is
because the client performs open() by checking the permissions, but UID
mapping is performed by the server upon read and write requests.
If the file is newly created, its st_atime, st_ctime, st_mtime fields
(respectively, time of last access, time of last status change, and
time of last modification; see stat(2)) are set to the current time,
and so are the st_ctime and st_mtime fields of the parent directory.
Otherwise, if the file is modified because of the O_TRUNC flag, its
st_ctime and st_mtime fields are set to the current time.
ERRORS
EACCES The requested access to the file is not allowed, or search per‐
mission is denied for one of the directories in the path prefix
of pathname, or the file did not exist yet and write access to
the parent directory is not allowed. (See also path_resolu‐
tion(2).)
EEXIST pathname already exists and O_CREAT and O_EXCL were used.
EFAULT pathname points outside your accessible address space.
EISDIR pathname refers to a directory and the access requested involved
writing (that is, O_WRONLY or O_RDWR is set).
ELOOP Too many symbolic links were encountered in resolving pathname,
or O_NOFOLLOW was specified but pathname was a symbolic link.
EMFILE The process already has the maximum number of files open.
ENAMETOOLONG
pathname was too long.
ENFILE The system limit on the total number of open files has been
reached.
ENODEV pathname refers to a device special file and no corresponding
device exists. (This is a Linux kernel bug; in this situation
ENXIO must be returned.)
ENOENT O_CREAT is not set and the named file does not exist. Or, a
directory component in pathname does not exist or is a dangling
symbolic link.
ENOMEM Insufficient kernel memory was available.
ENOSPC pathname was to be created but the device containing pathname
has no room for the new file.
ENOTDIR
A component used as a directory in pathname is not, in fact, a
directory, or O_DIRECTORY was specified and pathname was not a
directory.
ENXIO O_NONBLOCK | O_WRONLY is set, the named file is a FIFO and no
process has the file open for reading. Or, the file is a device
special file and no corresponding device exists.
EOVERFLOW
pathname refers to a regular file, too large to be opened; see
O_LARGEFILE above.
EPERM The O_NOATIME flag was specified, but the effective user ID of
the caller did not match the owner of the file and the caller
was not privileged (CAP_FOWNER).
EROFS pathname refers to a file on a read-only filesystem and write
access was requested.
ETXTBSY
pathname refers to an executable image which is currently being
executed and write access was requested.
EWOULDBLOCK
The O_NONBLOCK flag was specified, and an incompatible lease was
held on the file (see fcntl(2)).
NOTE
Under Linux, the O_NONBLOCK flag indicates that one wants to open but
does not necessarily have the intention to read or write. This is typ‐
ically used to open devices in order to get a file descriptor for use
with ioctl(2).
CONFORMING TO
SVr4, SVID, POSIX, X/OPEN, 4.3BSD. The O_NOATIME, O_NOFOLLOW, and
O_DIRECTORY flags are Linux-specific. One may have to define the
_GNU_SOURCE macro to get their definitions.
The (undefined) effect of O_RDONLY | O_TRUNC varies among implementa‐
tions. On many systems the file is actually truncated.
The O_DIRECT flag was introduced in SGI IRIX, where it has alignment
restrictions similar to those of Linux 2.4. IRIX has also a fcntl(2)
call to query appropriate alignments, and sizes. FreeBSD 4.x intro‐
duced a flag of same name, but without alignment restrictions. Support
was added under Linux in kernel version 2.4.10. Older Linux kernels
simply ignore this flag. One may have to define the _GNU_SOURCE macro
was added under Linux in kernel version 2.4.10. Older Linux kernels
simply ignore this flag. One may have to define the _GNU_SOURCE macro
to get its definition.
BUGS
"The thing that has always disturbed me about O_DIRECT is that the
whole interface is just stupid, and was probably designed by a deranged
monkey on some serious mind-controlling substances." — Linus
RESTRICTIONS
There are many infelicities in the protocol underlying NFS, affecting
amongst others O_SYNC and O_NDELAY.
POSIX provides for three different variants of synchronised I/O, corre‐
sponding to the flags O_SYNC, O_DSYNC and O_RSYNC. Currently (2.1.130)
these are all synonymous under Linux.
SEE ALSO
close(2), dup(2), fcntl(2), link(2), lseek(2), mknod(2), mount(2),
mmap(2), path_resolution(2), read(2), socket(2), stat(2), umask(2),
unlink(2), write(2), fopen(3), fifo(4)
Linux 2.6.12 2005-06-22 OPEN(2)
pcboyxhy 2006-10-19
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OPEN(2) Linux Programmer’s Manual OPEN(2)
NAME
open, creat - open and possibly create a file or device
SYNOPSIS
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
int open(const char *pathname, int flags);
int open(const char *pathname, int flags, mode_t mode);
int creat(const char *pathname, mode_t mode);
DESCRIPTION
Given a pathname for a file, open() returns a file descriptor, a small,
non-negative integer for use in subsequent system calls (read(2),
write(2), lseek(2), fcntl(2), etc.). The file descriptor returned by a
successful call will be the lowest-numbered file descriptor not cur‐
rently open for the process.
The new file descriptor is set to remain open across an execve(2)
(i.e., the FD_CLOEXEC file descriptor flag described in fcntl(2) is
initially disabled). The file offset is set to the beginning of the
file (see lseek(2)).
A call to open() creates a new open file description, an entry in the
system-wide table of open files. This entry records the file offset
and the file status flags (modifiable via the fcntl() F_SETFL opera‐
tion). A file descriptor is a reference to one of these entries; this
reference is unaffected if pathname is subsequently removed or modified
to refer to a different file. The new open file description is ini‐
tially not shared with any other process, but sharing may arise via
fork(2).
The parameter flags must include one of the following access modes:
O_RDONLY, O_WRONLY, or O_RDWR. These request opening the file read-
only, write-only, or read/write, respectively. In addition, zero or
more of the following may be bitwise-or’d in flags:
O_APPEND
The file is opened in append mode. Before each write(), the file
offset is positioned at the end of the file, as if with lseek().
O_APPEND may lead to corrupted files on NFS file systems if more
than one process appends data to a file at once. This is
because NFS does not support appending to a file, so the client
kernel has to simulate it, which can’t be done without a race
condition.
O_ASYNC
Generate a signal (SIGIO by default, but this can be changed via
fcntl(2)) when input or output becomes possible on this file
descriptor. This feature is only available for terminals,
pseudo-terminals, sockets, and (since Linux 2.6) pipes and
FIFOs. See fcntl(2) for further details.
O_CREAT
If the file does not exist it will be created. The owner (user
ID) of the file is set to the effective user ID of the process.
The group ownership (group ID) is set either to the effective
group ID of the process or to the group ID of the parent direc‐
tory (depending on filesystem type and mount options, and the
mode of the parent directory, see, e.g., the mount options bsd‐
groups and sysvgroups of the ext2 filesystem, as described in
mount(8)).
O_DIRECT
Try to minimize cache effects of the I/O to and from this file.
In general this will degrade performance, but it is useful in
special situations, such as when applications do their own
caching. File I/O is done directly to/from user space buffers.
The I/O is synchronous, i.e., at the completion of a read(2) or
write(2), data is guaranteed to have been transferred. Under
Linux 2.4 transfer sizes, and the alignment of user buffer and
file offset must all be multiples of the logical block size of
the file system. Under Linux 2.6 alignment to 512-byte bound‐
aries suffices.
A semantically similar interface for block devices is described
in raw(8).
O_DIRECTORY
If pathname is not a directory, cause the open to fail. This
flag is Linux-specific, and was added in kernel version 2.1.126,
to avoid denial-of-service problems if opendir(3) is called on a
FIFO or tape device, but should not be used outside of the
implementation of opendir.
O_EXCL When used with O_CREAT, if the file already exists it is an
error and the open() will fail. In this context, a symbolic link
exists, regardless of where it points to. O_EXCL is broken on
NFS file systems; programs which rely on it for performing lock‐
ing tasks will contain a race condition. The solution for per‐
forming atomic file locking using a lockfile is to create a
unique file on the same file system (e.g., incorporating host‐
name and pid), use link(2) to make a link to the lockfile. If
link() returns 0, the lock is successful. Otherwise, use
stat(2) on the unique file to check if its link count has
increased to 2, in which case the lock is also successful.
O_LARGEFILE
(LFS) Allow files whose sizes cannot be represented in an off_t
(but can be represented in an off64_t) to be opened.
O_NOATIME
(Since Linux 2.6.8) Do not update the file last access time
(st_atime in the inode) when the file is read(2). This flag is
intended for use by indexing or backup programs, where its use
can significantly reduce the amount of disk activity. This flag
may not be effective on all filesystems. One example is NFS,
where the server maintains the access time.
O_NOCTTY
If pathname refers to a terminal device — see tty(4) — it will
not become the process’s controlling terminal even if the pro‐
cess does not have one.
O_NOFOLLOW
If pathname is a symbolic link, then the open fails. This is a
FreeBSD extension, which was added to Linux in version 2.1.126.
Symbolic links in earlier components of the pathname will still
be followed.
O_NONBLOCK or O_NDELAY
When possible, the file is opened in non-blocking mode. Neither
the open() nor any subsequent operations on the file descriptor
which is returned will cause the calling process to wait. For
the handling of FIFOs (named pipes), see also fifo(4). This
mode need not have any effect on files other than FIFOs.
O_SYNC The file is opened for synchronous I/O. Any write()s on the
resulting file descriptor will block the calling process until
the data has been physically written to the underlying hardware.
See RESTRICTIONS below, though.
O_TRUNC
If the file already exists and is a regular file and the open
mode allows writing (i.e., is O_RDWR or O_WRONLY) it will be
truncated to length 0. If the file is a FIFO or terminal device
file, the O_TRUNC flag is ignored. Otherwise the effect of
O_TRUNC is unspecified.
NAME
open, creat - open and possibly create a file or device
SYNOPSIS
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
int open(const char *pathname, int flags);
int open(const char *pathname, int flags, mode_t mode);
int creat(const char *pathname, mode_t mode);
DESCRIPTION
Given a pathname for a file, open() returns a file descriptor, a small,
non-negative integer for use in subsequent system calls (read(2),
write(2), lseek(2), fcntl(2), etc.). The file descriptor returned by a
successful call will be the lowest-numbered file descriptor not cur‐
rently open for the process.
The new file descriptor is set to remain open across an execve(2)
(i.e., the FD_CLOEXEC file descriptor flag described in fcntl(2) is
initially disabled). The file offset is set to the beginning of the
file (see lseek(2)).
A call to open() creates a new open file description, an entry in the
system-wide table of open files. This entry records the file offset
and the file status flags (modifiable via the fcntl() F_SETFL opera‐
tion). A file descriptor is a reference to one of these entries; this
reference is unaffected if pathname is subsequently removed or modified
to refer to a different file. The new open file description is ini‐
tially not shared with any other process, but sharing may arise via
fork(2).
The parameter flags must include one of the following access modes:
O_RDONLY, O_WRONLY, or O_RDWR. These request opening the file read-
only, write-only, or read/write, respectively. In addition, zero or
more of the following may be bitwise-or’d in flags:
O_APPEND
The file is opened in append mode. Before each write(), the file
offset is positioned at the end of the file, as if with lseek().
O_APPEND may lead to corrupted files on NFS file systems if more
than one process appends data to a file at once. This is
because NFS does not support appending to a file, so the client
kernel has to simulate it, which can’t be done without a race
condition.
O_ASYNC
Generate a signal (SIGIO by default, but this can be changed via
fcntl(2)) when input or output becomes possible on this file
descriptor. This feature is only available for terminals,
pseudo-terminals, sockets, and (since Linux 2.6) pipes and
FIFOs. See fcntl(2) for further details.
O_CREAT
If the file does not exist it will be created. The owner (user
ID) of the file is set to the effective user ID of the process.
The group ownership (group ID) is set either to the effective
group ID of the process or to the group ID of the parent direc‐
tory (depending on filesystem type and mount options, and the
mode of the parent directory, see, e.g., the mount options bsd‐
groups and sysvgroups of the ext2 filesystem, as described in
mount(8)).
O_DIRECT
Try to minimize cache effects of the I/O to and from this file.
In general this will degrade performance, but it is useful in
special situations, such as when applications do their own
caching. File I/O is done directly to/from user space buffers.
The I/O is synchronous, i.e., at the completion of a read(2) or
write(2), data is guaranteed to have been transferred. Under
Linux 2.4 transfer sizes, and the alignment of user buffer and
file offset must all be multiples of the logical block size of
the file system. Under Linux 2.6 alignment to 512-byte bound‐
aries suffices.
A semantically similar interface for block devices is described
in raw(8).
O_DIRECTORY
If pathname is not a directory, cause the open to fail. This
flag is Linux-specific, and was added in kernel version 2.1.126,
to avoid denial-of-service problems if opendir(3) is called on a
FIFO or tape device, but should not be used outside of the
implementation of opendir.
O_EXCL When used with O_CREAT, if the file already exists it is an
error and the open() will fail. In this context, a symbolic link
exists, regardless of where it points to. O_EXCL is broken on
NFS file systems; programs which rely on it for performing lock‐
ing tasks will contain a race condition. The solution for per‐
forming atomic file locking using a lockfile is to create a
unique file on the same file system (e.g., incorporating host‐
name and pid), use link(2) to make a link to the lockfile. If
link() returns 0, the lock is successful. Otherwise, use
stat(2) on the unique file to check if its link count has
increased to 2, in which case the lock is also successful.
O_LARGEFILE
(LFS) Allow files whose sizes cannot be represented in an off_t
(but can be represented in an off64_t) to be opened.
O_NOATIME
(Since Linux 2.6.8) Do not update the file last access time
(st_atime in the inode) when the file is read(2). This flag is
intended for use by indexing or backup programs, where its use
can significantly reduce the amount of disk activity. This flag
may not be effective on all filesystems. One example is NFS,
where the server maintains the access time.
O_NOCTTY
If pathname refers to a terminal device — see tty(4) — it will
not become the process’s controlling terminal even if the pro‐
cess does not have one.
O_NOFOLLOW
If pathname is a symbolic link, then the open fails. This is a
FreeBSD extension, which was added to Linux in version 2.1.126.
Symbolic links in earlier components of the pathname will still
be followed.
O_NONBLOCK or O_NDELAY
When possible, the file is opened in non-blocking mode. Neither
the open() nor any subsequent operations on the file descriptor
which is returned will cause the calling process to wait. For
the handling of FIFOs (named pipes), see also fifo(4). This
mode need not have any effect on files other than FIFOs.
O_SYNC The file is opened for synchronous I/O. Any write()s on the
resulting file descriptor will block the calling process until
the data has been physically written to the underlying hardware.
See RESTRICTIONS below, though.
O_TRUNC
If the file already exists and is a regular file and the open
mode allows writing (i.e., is O_RDWR or O_WRONLY) it will be
truncated to length 0. If the file is a FIFO or terminal device
file, the O_TRUNC flag is ignored. Otherwise the effect of
O_TRUNC is unspecified.
jixingzhong 2006-10-19
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open 是在 Unix/Linux 下的，
没有被包含在标准C库中。
fopen 和 open 虽然都是打开文件，
但是它们对文件的操作方式不一样，
没有可比性。
fopen 返回一个文件结构体指针， 也就是你说的地址；
open 返回的是一个 文件的 handle， 正确的情况下是 非0 值。
没有被包含在标准C库中。
fopen 和 open 虽然都是打开文件，
但是它们对文件的操作方式不一样，
没有可比性。
fopen 返回一个文件结构体指针， 也就是你说的地址；
open 返回的是一个 文件的 handle， 正确的情况下是 非0 值。
飞哥 2006-10-19
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linux C 系统调用函数
～～～～～～～回答完毕！◎！
～～～～～～～回答完毕！◎！
lann64 2006-10-19
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请问一句open函数是标准C的库函数？
只见过fopen,freopen,没见过open呢。
只见过fopen,freopen,没见过open呢。
飞哥 2006-10-19
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楼上这位太强了
个人建议楼上的第二种方法
最好来个 replace all
个人建议楼上的第二种方法
最好来个 replace all
DanielWYO 2006-10-19
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最简单的方法: #define open fopen
复杂的方法: 使用寻找/替换工具来替换掉好了
