readlink - 讀符號連結的值
內容簡介
#include <unistd.h>
ssize_t readlink(const char *path, char *buf, size_t bufsiz);
描述
readlink() places the contents of the symbolic link path in the buffer buf, which has sizebufsiz. readlink() does not append a null byte to buf. It will truncate the contents (to a length of bufsiz characters), in case the buffer is too small to hold all of the contents.
返回值
The call returns the count of characters placed in the buffer if it succeeds, or a -1 if an error occurs, placing the error code in errno.
錯誤
|
標籤 |
描述 |
|
EACCES |
搜尋許可權的路徑字首的組成部分將被拒絕. (See also path_resolution(2).) |
|
EFAULT |
buf 進程的已分配地址空間之外延伸. |
|
EINVAL |
bufsiz is not positive. |
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EINVAL |
The named file is not a symbolic link. |
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EIO |
An I/O error occurred while reading from the file system. |
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ELOOP |
Too many symbolic links were encountered in translating the pathname. |
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ENAMETOOLONG |
|
|
路徑名，或路徑名的組成部分太長。 |
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ENOENT |
指定的檔案不存在。 |
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ENOMEM |
沒有足夠的核心記憶體可用。 |
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ENOTDIR |
|
|
路徑字首的某組成部分不是目錄。 |
遵循於
4.4BSD (the readlink() function call appeared in 4.2BSD), POSIX.1-2001.
HISTORY
In versions of glibc up to and including glibc 2.4, the return type of readlink() was declared as int. Nowadays, the return type is declared as ssize_t, as (newly) required in POSIX.1-2001.
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