如何查找Linux的函数定义的位置？

网上的许多站点提供这样的服务，如下面这个：

http://lxr.free-electrons.com/ident?v=3.10

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Linux的错误返回值：3.10版本

Linux/include/uapi/asm-generic/errno-base.h

#ifndef _ASM_GENERIC_ERRNO_BASE_H
#define _ASM_GENERIC_ERRNO_BASE_H

#define    EPERM         1    /* Operation not permitted */
#define    ENOENT         2    /* No such file or directory */
#define    ESRCH         3    /* No such process */
#define    EINTR         4    /* Interrupted system call */
#define    EIO         5    /* I/O error */
#define    ENXIO         6    /* No such device or address */
#define    E2BIG         7    /* Argument list too long */
#define    ENOEXEC         8    /* Exec format error */
#define    EBADF         9    /* Bad file number */
#define    ECHILD        10    /* No child processes */
#define    EAGAIN        11    /* Try again */
#define    ENOMEM        12    /* Out of memory */
#define    EACCES        13    /* Permission denied */
#define    EFAULT        14    /* Bad address */
#define    ENOTBLK        15    /* Block device required */
#define    EBUSY        16    /* Device or resource busy */
#define    EEXIST        17    /* File exists */
#define    EXDEV        18    /* Cross-device link */
#define    ENODEV        19    /* No such device */
#define    ENOTDIR        20    /* Not a directory */
#define    EISDIR        21    /* Is a directory */
#define    EINVAL        22    /* Invalid argument */
#define    ENFILE        23    /* File table overflow */
#define    EMFILE        24    /* Too many open files */
#define    ENOTTY        25    /* Not a typewriter */
#define    ETXTBSY        26    /* Text file busy */
#define    EFBIG        27    /* File too large */
#define    ENOSPC        28    /* No space left on device */
#define    ESPIPE        29    /* Illegal seek */
#define    EROFS        30    /* Read-only file system */
#define    EMLINK        31    /* Too many links */
#define    EPIPE        32    /* Broken pipe */
#define    EDOM        33    /* Math argument out of domain of func */
#define    ERANGE        34    /* Math result not representable */

#endif

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