问个入门问题

引用:

. ~/.bash_aliases

levee 写道:

这一句，如果不加.将启动一个子shell解释并执行.bash_aliases文件，加了.就在当前shell解释并执行.bash_aliases。

引用:

. file
The commands in the specified file are read and executed by the shell.

引用:

. filename [arguments]
source filename [arguments]
Read and execute commands from filename in the current shell environ‐
ment and return the exit status of the last command executed from
filename. If filename does not contain a slash, file names in PATH
are used to find the directory containing filename. The file
searched for in PATH need not be executable. When bash is not in
posix mode, the current directory is searched if no file is found in
PATH. If the sourcepath option to the shopt builtin command is
turned off, the PATH is not searched. If any arguments are supplied,
they become the positional parameters when filename is executed.
Otherwise the positional parameters are unchanged. The return status
is the status of the last command exited within the script (0 if no
commands are executed), and false if filename is not found or cannot
be read.

引用:

. file [ arg ... ]
Read commands from file and execute them in the current shell envi‐
ronment.

If file does not contain a slash, or if PATH_DIRS is set, the shell
looks in the components of $path to find the directory containing
file. Files in the current directory are not read unless `.' appears
somewhere in $path. If a file named `file.zwc' is found, is newer
than file, and is the compiled form (created with the zcompile
builtin) of file, then commands are read from that file instead of
file.

If any arguments arg are given, they become the positional parame‐
ters; the old positional parameters are restored when the file is
done executing. The exit status is the exit status of the last com‐
mand executed.