can't get whole command line on AIX platform

[slqt]

It may have error on all aix system,I guess.I run was and want get was's commad line on AIX 6.1 system,but I only can get little infomation of the whole command line .You can test the program with code below,11534558 is the process's pid :
`import psutil

proc=psutil.Process(11534558)

pidDictionary = proc.as_dict(attrs=['cmdline'])

print pidDictionary
`

[wiggin15]

I'm not sure I understand the problem correctly, but there is a known issue in AIX (and Solaris) that causes very long arguments in the command line to be "skipped" from Process.cmdline. See, for example, bullet 2 in this comment: #605 (comment).
and it's actually a test that is being skipped (https://github.com/giampaolo/psutil/blob/master/psutil/tests/test_process.py#L725).

If you run "ps", does it show the command line as you expect?

[slqt]

Thank you for the answer.
I can get the correct respond with the command 'ps -ef' on AIX,but can't with the command 'ps aux','ps -a' and 'ps'.Maybe you can use 'ps -ef' instead to get the whole process info.
I don't know why.I faced this problem when I use python to run and test the WebSphere's process on AIX,because was's pocess is very long.

[sandrotosi]

I have the same issue: the output from Process.cmdline() on AIX seems to be a list, split by spaces, of an 80-char string (try to len(' '.join(p.cmdline()), i get 79 when it's on a truncated cmdline process).

i can read the full command-line while running ps -edaf

[wiggin15]

There are two problems with long command lines on AIX:

• Very long arguments are truncated and apparently cannot be retrieved, not with ps or any other method. They seem to be replaced with the previous argument instead. For example:

~ python -c "import time; time.sleep(1000)" &                                                                                                                                                  19-04-16 12:06
[1] 12059122
~ ps aux | grep python                                                                                                                                                                         19-04-16 12:06
root     12059122  0.0  0.0 1948 2012  pts/0 A    12:06:12  0:00 python -c -c
~ ps -edaf | grep python                                                                                                                                                                       19-04-16 12:06
    root 12059122  9044312   0 12:06:12  pts/0  0:00 python -c -c

In this case the argument import time; time.sleep(1000) is replaced with -c for some reason, and I can't find a way to get it.

• A very long line is truncated in psutil and ps aux but not truncated by ps -ef:

~ python -c "import time; time.sleep(1000)" -c aaaaa  -c aaaaa  -c aaaaa  -c aaaaa -c aaaaa  -c aaaaa  -c aaaaa  -c aaaaa &                                                                    19-04-16 12:08
[1] 12059126
~ ps aux | grep python                                                                                                                                                                         19-04-16 12:08
root     12059126  0.0  0.0 1948 2012  pts/0 A    12:08:45  0:00 python -c -c -
~ ps -ef | grep python                                                                                                                                                                         19-04-16 12:08
    root 12059126  9044312   0 12:08:45  pts/0  0:00 python -c -c -c aaaaa -c aaaaa -c aaaaa -c aaaaa -c aaaaa -c aaaaa -c aaaaa -c aaaaa

ps -ef will truncate the same long parameter, but not the rest of the long line.

The latter case can be fixed in psutil by using getargs. Here is an example of how to use it:

void print_pid_args(int pid)
{
    char buf[8192];
    struct procsinfo procbuf;
    char *p = buf;
    procbuf.pi_pid = pid;

    getargs(&procbuf, sizeof(struct procinfo), buf,sizeof(buf));
    while (*p != '\0') {
        printf("%s ", p);
        p = strchr(p, '\0') + 1;
    }
}

[giampaolo]

It looks like getargs is a win indeed and it probably should be used instead of reading /proc/pid/psinfo:

psutil/psutil/_psutil_aix.c

Lines 151 to 158 in 7a3037e

	sprintf(path, "%s/%i/psinfo", procfs_path, pid);
	if (! psutil_file_to_struct(path, (void *)&info, sizeof(info)))
	return NULL;
	py_name = PyUnicode_DecodeFSDefault(info.pr_fname);
	if (!py_name)
	goto error;
	py_args = PyUnicode_DecodeFSDefault(info.pr_psargs);

From:
https://sites.ualberta.ca/dept/chemeng/AIX-43/share/man/info/C/a_doc_lib/libs/basetrf1/getargs.htm
...looks like EBADF should be used as an alias for NoSuchProcess. Not sure what happens in case of permission error (I would expect something like EACCES but it's not mentioned in the man page).

[wiggin15]

Actually this is the correct documentation page for getargs:
https://www.ibm.com/support/knowledgecenter/ru/ssw_aix_72/com.ibm.aix.basetrf1/getargs.htm
errno will be ESRCH if the process is not found.