Commands often generate error messages because of permission restrictions that are not obvious permission problems; for example, you may get a message similar to Unable to execute command or Could not access file .
In general, you should have read permission for the file you use as input, write permission for the file you enter information in, and execute permission for the command you use. Some commands can be run only by the root user. See the following to recover from file and directory permission errors:
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To recover from read and write permission errors, do the following:
Output similar to the following is displayed for each file or directory specified:
-rwxr-xr-x 1 root system 26 Sept 25 12:57 this_one
ls -l FileName
To add write permission on the file or directory, enter the chmod +w Name command. If you cannot change write permission, use the su command to change to the root user or to the owner of the file or directory, and reenter chmod +w Name.
Ask the owner of the file or directory to use the chmod command to give you read and/or write permission.
Note: You can also specify numeric arguments with the chmod command to set permissions on a file or directory for individual groups or users. For example, the chmod 777 Name command enables all permissions on a file or directory. See the "Numeric or Absolute Mode" section in the chmod command for more information.
If you cannot find the solution to your problem in these articles, return to "Recovering from Software Errors".
To locate the command and check it for execute permissions, do the following:
If you cannot change execute permission, use the su command to change to the root user or to the owner of the file or directory, and reenter chmod +x Name.
Ask the owner of the file or directory to use the chmod command to provide you with execute permission.
Note: You can also specify numeric arguments with the chmod command to set permissions on a file or directory for individual groups or users. For example, the chmod 777 Name command enables all permissions on a file or directory. See the "Numeric or Absolute Mode" section in the chmod command for more information.
If you cannot find the solution to your problem in these articles, return to "Recovering from Software Errors".