sem_open can't open a name with directory

 

sem_open can't open a name with directory

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• From: "Xiong, Crystal" <crystal xiong intel com>
• To: phil-list redhat com
• Subject: sem_open can't open a name with directory
• Date: Tue, 28 Jan 2003 21:00:54 +0800

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Title: Message

If define name as "/tmp/xxxx", and invoke sem_open(name, flag...), sem_open will failed with "No such file or directory". 

 

Looked into the code sem_open.c, the reason is that the name ("/tmp/xxxx")will map to /dev/shm/sem.tmp/xxxx, but sem.tmp directory is not there, so there will be an error.

 

I think in sem_open.c, it maybe needs a check of whether name has more slash characters other than the leading slash character.

If it has, mkdir the related directory before rename operation (sem_open.c:234), such as the following:

    tmpname = strrchr(finalname, '/');  // get the file name without directory

    strncpy(pathname, finalname, strlen(finalname) - strlen(tmpname)); // get the directory path

    mkdir(pathname, 0777)

 

To the POSIX std, it says the interpretation of slash characters other than the leading slash character in name is implementaion defined. I think it will be more friendly to allow the user using a name with directory.

 

Thanks,

Crystal

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This is only my personal opinion.

 

Crystal Xiong

Intel China Software Lab