c - lseek EOVERFLOW 错误处理

Question

我注意到，当我尝试寻找比 off_t 所能代表的更多的字节时，我得到了EOVERFLOW 错误。我怎样才能在 off_t 中寻找更大的数字？

Answer 1

启用large file support .

In a nutshell for using LFS you can choose either of the following:

• Compile your programs with "gcc -D_FILE_OFFSET_BITS=64". This forces all file access calls to use the 64 bit variants. Several types change also, e.g. off_t becomes off64_t. It's therefore important to always use the correct types and to not use e.g. int instead of off_t. For portability with other platforms you should use getconf LFS_CFLAGS which will return -D_FILE_OFFSET_BITS=64 on Linux platforms but might return something else on e.g. Solaris. For linking, you should use the link flags that are reported via getconf LFS_LDFLAGS. On Linux systems, you do not need special link flags.
• Define _LARGEFILE_SOURCE and _LARGEFILE64_SOURCE. With these defines you can use the LFS functions like open64 directly.
• Use the O_LARGEFILE flag with open to operate on large files.