The absence of relevant file execute permissions
Solution:
The first step :( command window to enter commands)
chmod u+x *.sh
The second step :( command window to start the command again)
cd /home/homework/mysql && ./start.sh
Mysql to start normal;
Chmod Detailed
chmod: file / directory permissions command
This command is used to change the file or directory access. This command is used in two ways:
Method a: Method set comprising words and letters operator expressions
which syntax is: chmod [who] [opt] [mode] file / directory name
who representing an object, or a combination of the following letters:
u: User, that is, the owner of the file or directory.
g: Group, that is, their group of files or directories.
o: Other, except for the file or directory owner, or their group, others belong to this range.
a: All, that is, all users including owner, owning group, and other users.
opt is representative of operation, can be:
+: Add a permission
-: cancel a privilege
=: given given permission, and permission to cancel the original
represents permission mode:
R & lt: read
w: write
x: Executable
Example: chmod u + x * .sh
Method 2: digital setting method
which syntax is: chmod [mode] File Name
Mode wherein the threshold is a combination of three arrays Arab, particularly on behalf of the following meanings:
Users manipulate files or directories, there are three different types: file owner, group, user, other users. MSB value represents the permissions of the file owner, the middle bit represents a group of users permission value, the lowest bit indicates other authority value of the user, so the chmod 777, three numbers above 7 correspond to three user permissions values 7.
Permissions on the file or directory is divided into three kinds: read-only, write-only, executable.
| Competence | Permissions value | Binary | Specific role |
|---|---|---|---|
| r | 4 | 00000100 | read, read. The current user can read the contents of the file, the current user can browse the directory. |
| w | 2 | 00000010 | write, write. The current user can add or modify the contents of the file, the current user can delete, move, or directory within the directory file. |
| x | 1 | 00000001 | execute, execute. The current user can execute the file, the current user can access the directory. |
In accordance with the above table, it is a combination of rights authority value corresponding to the sum, as follows:
7 = 4 + 2 + 1 write permission to run
the read 4 + 1 = 5 and the permission to run
4 = 4 read-only permissions
Example: chmod 644 test.txt