From time to time, we might see some files on Linux which have strange leading characters. For example, a leading “-” dash or a leading “+” plus sign. Depending on which operations (which commands) you take, you may have different ways to handle those files — putting file name in a single or double quotes, escaping the special character with “\” etc so that commands can handle them properly — not treated as an option, but files to be processed.
[grid@eiagc1oda001 trace]$ ls -l +APX1_ora_1557.trc -rw-r----- 1 grid oinstall 939 May 8 10:37 +APX1_ora_1557.trc [grid@eiagc1oda001 trace]$ less +APX1_ora_1557.trc Missing filename ("less --help" for help)
In BASH, there is actually an official way to disable further option processing. “man bash” will show the usage of “–“
— A — signals the end of options and disables further option processing. Any arguments after the — are treated as filenames and arguments. An argument of – is equivalent to –.
[grid@joeoda001 trace]$ ls -lrt -- *abc* -rw-r--r-- 1 grid oinstall 0 May 11 15:25 -abc_test [grid@joeoda001 trace]$ rm -- -abc_test [grid@joeoda001 trace]$ less -- +APX1_ora_1557.trc
Examples above show files starting with “-” or “+” operated by “ls” and “less”.