You need to check your use of disk space periodically to be sure you won't run out of room. Reduce the size of mail files with delete and expunge to keep them from growing too large.
MM normally keeps all your mail in a file named mbox, and the last previous version of mbox is kept in a file named mbox~ as a backup. This means you need enough disk space to keep two copies of mbox.
One of the things shown by the status command is the size of mbox.
MM>status File /f/u1/d00000/jb51/mbox (mbox) 80 messages, 70 old, 6 deleted, 5 unseen, 257k Bytes Currently at message 75
The UNIX shell command ls shows what files you have in your directory. If the only work you have done is with MM, the ls command will show something like this:
$ ls mbox mbox~ $
The above shows that there are only two files, mbox and mbox~. If you created any other files, they would also be listed.
UNIX shell commands often have options that you can specify by a minus sign and a letter. One option to ls is -s, which shows file size:
$ ls -s total 514 257 mbox 257 mbox~ $
The size is given in kilobytes. A kilobyte (k) is 1,024 bytes, and each byte represents one character, such as a letter, number, punctuation mark or blank.
Often, as shown here, mbox and mbox~ are the same size; even though mbox~ is the previous version of mbox, the difference might be rather minor, as for example some messages might be unseen in mbox~ and seen in mbox. The example above shows 514 kilobytes used, 257 in each file, and no other files.
The command du shows how much disk space a directory uses. The size is given in kilobytes.
$ du 527 . $
Both du and ls -s show how much space your files are taking up, but you need also to remember how much space you are allowed to use. To verify your quota, you can use the quota command. You need to use the option -v. The result varies on different systems but is something like this:
$ quota -v Disk quotas for jb51 (uid 8988): Filesystem usage quota limit timeleft files quota limit timeleft /spool 0 512 512 0 1280 1280 /temp 0 1000 1000 0 2500 2500 /f/u1 527 1024 1024 9 1280 1280 $
The output above shows quotas for three filesystems. The first two, /spool and /temp, are for temporary use; /spool is where incoming mail accumulates before MM brings it into your mail file. The last line shows the use of 527k out of a quota of 1024k, so in this example there is a reasonable amount of space left.