“设备的不适当的ioctl" [英] "inappropriate ioctl for device"

问题描述

我在AIX框中运行一个Perl脚本.

I have a Perl script running in an AIX box.

该脚本尝试从某个目录打开文件，但由于文件没有读取权限，因此无法读取该文件，但是出现了另一个错误，提示inappropriate ioctl for device.

The script tries to open a file from a certain directory and it fails to read the file because file has no read permission, but I get a different error saying inappropriate ioctl for device.

它不是应该说类似no read permissions for file之类的话吗?

Shouldn't it say something like no read permissions for file or something similar?

此inappropriate ioctl for device消息是什么意思?

我该如何解决?

这是我做strace时发现的.

open("/local/logs/xxx/xxxxServer.log", O_WRONLY|O_CREAT|O_APPEND|O_LARGEFILE, 
    0666) = 4 _llseek(4, 0, [77146], SEEK_END) = 0
ioctl(4, SNDCTL_TMR_TIMEBASE or TCGETS, 0xbffc14f8) = -1 ENOTTY 
    (Inappropriate ioctl for  device)

推荐答案

最有可能意味着打开的不会失败.

Most likely it means that the open didn't fail.

当Perl打开文件时，它将通过向文件发出TCGETS ioctl来检查该文件是否为TTY(以便它可以回答-T $fh filetest运算符).如果文件是常规文件而不是tty，则ioctl失败并将errno设置为ENOTTY(字符串值:设备的不适当的ioctl").如ysth所说，在$!中看到意外值的最常见原因是在无效时进行检查-即在 other 以外的地方，而不是在系统调用失败后立即进行检查，因此测试结果代码您的运营至关重要.

When Perl opens a file, it checks whether or not the file is a TTY (so that it can answer the -T $fh filetest operator) by issuing the TCGETS ioctl against it. If the file is a regular file and not a tty, the ioctl fails and sets errno to ENOTTY (string value: "Inappropriate ioctl for device"). As ysth says, the most common reason for seeing an unexpected value in $! is checking it when it's not valid -- that is, anywhere other than immediately after a syscall failed, so testing the result codes of your operations is critically important.

如果open实际上确实为您返回了false，并且您在$!中找到了ENOTTY，那么我会认为这是一个小错误(给出了$!的无用值)，但我也很好奇怎么发生的.代码和/或桁架输出会很漂亮.

If open actually did return false for you, and you found ENOTTY in $! then I would consider this a small bug (giving a useless value of $!) but I would also be very curious as to how it happened. Code and/or truss output would be nifty.

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