问题
I know that exit code = 0 means No error.
I got exit code = 2. What does it means ?
Where I can see the complete list of mysqldump exit codes ?
回答1:
Taken from client/mysqldump.c in MySQL 5.1.59:
#define EX_USAGE 1
#define EX_MYSQLERR 2
#define EX_CONSCHECK 3
#define EX_EOM 4
#define EX_EOF 5 /* ferror for output file was got */
#define EX_ILLEGAL_TABLE 6
Skimming through the source, EX_MYSQLERR seems to be used mostly for errors from the server, but also in case malloc fails. CONSCHECK seems to stand for consistency checks. EX_EOM is returned for some _alloc calls too - "End Of Memory"?
回答2:
Exit code 2 often occurs when the dump could not be completed due to privilege problems; for example, if the user does not have the LOCK TABLES privilege, or the supplied password was wrong.
回答3:
This is worth noting that if you use mysqldump in php function exec, shell_exec or system as command it will return 02 exit code if you do not have permissions to write file into selected location.
In my case command:
mysqldump '-uUSER' '-pPASS' DATABASE > /home/USER/LOCATION/dump.sql
When called from php did not work. It was solved after adding proper write permissions to LOCATION folder.
I solved it by checking what was sent as output when calling command:
myslqdump
and after it:
mysqldump '-uUSER' '-pPASS' DATABASE
In both cases command gave proper response in 2nd argument of exec function.
回答4:
Another reason might be a password with too special chars, which was used unescaped on the console (since you use mysqldump). The process returns the error code 2 too. I have this problem from time to time. Wrapping params at least in quotes / double-quotes helps often: Instead -u... -p... and so on, using "-u..." "-p..." eliminates many problems. However it is not a perfect solution (if the same type of quotes are used).
It can also be an OS dependent problem. MS Windows for example uses variables, like %MYVAR% which seems not be able to be escaped at all (at least some sources like the PHP docu mentions this).
来源：https://stackoverflow.com/questions/3846022/where-i-can-find-a-list-of-mysqldump-exit-codes