How to view and add path environment variables under Linux

$PATH: determines which directories the shell will look for commands or programs, and the PATH value is a series of directories that Linux searches for and compiles links to when you run a program.

Edit your PATH declaration in the form of:

Path= $PATH: <path 1>:<path 2>:<path 3>:------: <path n>

You can add the specified path yourself, separated by a colon in the middle. When the environment variable is changed, it will take effect the next time the user logs on, and if you want to take effect immediately, you can execute the following statement: $ source. bash_profile

It should be noted that it is best not to put the current path "./" Into the path, which may be subject to unexpected attacks. When you are done, you can view the current search path through the $ echo $PATH. With this customization, you can avoid frequent startup of programs located outside the path of the shell search.

Use the Export command to view the path value

[Root@localhost u-boot-sh4]# Export

Declare-x cvs_rsh= "SSH"

Declare-x display= ": 0.0"

Declare-x g_broken_filenames= "1"

Declare-x histsize= "1000"

Declare-x home= "/root"

Declare-x hostname= "localhost"

Declare-x inputrc= "/ETC/INPUTRC"

Declare-x lang= "ZH_CN. UTF-8 "

Declare-x lessopen= "|/usr/bin/lesspipe.sh% s"

Declare-x logname= "Root"

Declare-x ls_colors= "NO=00:FI=00:DI=00;34:LN=00;36:PI=40;33:SO=00;35:BD=40;33;01:CD=40;33;01:OR=01;05; 37;41:mi= 01;05;37;41:ex=00;32:*.cmd=00;32:*.exe=00;32:*.com=00;32:*.btm=00;32:*.bat=00;32:*.sh= 00;32:*.csh=00;32:*.tar= 00;31:*.tgz=00;31:*.arj=00;31:*.taz=00;31:*.lzh=00;31:*.zip=00;31:*.z=00; 31:*. Z=00;31:*.GZ=00;31:*.BZ2=00;31:*.BZ=00;31:*.TZ=00;31:*.RPM=00;31:*.CPIO=00;31:*.JPG=00;35: *.gif=00;35:*.bmp=00 ; 35:*.xbm=00;35:*.xpm=00;35:*.png=00;35:*.tif=00;35: "

Declare-x mail= "/var/spool/mail/root"

Declare-x oldpwd= "/root"

Declare-xpath= "/usr/kerberos/sbin:/usr/kerberos/bin:/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/ Bin:/root/bin "

Declare-x pwd= "/opt/stm/stlinux-2.3/devkit/sources/u-boot/u-boot-sh4"

Declare-x shell= "/bin/bash"

Declare-x shlvl= "1"

Declare-x ssh_askpass= "/usr/libexec/openssh/gnome-ssh-askpass"

Declare-x term= "Xterm"

Declare-x user= "Root"

Declare-x xauthority= "/root/.xauthkszh7b"