How to determine if a file descriptor is seekable?
Is there any portable way (on POSIX systems) to determine if a file descriptor is seekable? My thought is to use `lseek(fd, 0, SEEK_CUR);` and check if the return value is -1, but I'm uncertain if this could give false negatives or false positives. Using `fstat` and making assumptions about what types of files are seekable/nonseekable does not sound like a good idea. Any other ideas?
How to determine if a file descriptor is seekable?
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Is there any portable way (on POSIX systems) to determine if a file descriptor is seekable? My thought is to use `lseek(fd, 0, SEEK_CUR);` and check if the return value is -1, but I'm uncertain if this could give false negatives or false positives. Using `fstat` and making assumptions about what types of files are seekable/nonseekable does not sound like a good idea. Any other ideas?