Difference between revisions of "BASH/C2/Globbing-and-Export-statement/English-timed"

|Welcome to this spoken tutorial on '''Globbing and Export command'''

|In this tutorial, we will learn about

|* '''export command'''

| To follow this tutorial, You should be familiar with '''Linux Operating System'''

|If not, for relevant tutorials please visit our  website which is are shown.

|For this tutorial I am using  

| Please note '''GNU Bash '' 'version '''4''' or above is recommended to practise this tutorial.

|* ''Filename'' or ''pathname'' expansion carried by '''BASH''' is known as '''Globbing'''.  

|* '''Globbing''' recognizes and expands '''wildcards.'''  

|* It also interprets standard '''wildcard''' characters like  

| # <nowiki>* </nowiki>'''(asterix) '''and

|# '''? (Question mark)'''

|Open the terminal window by pressing '''Ctrl+Alt''' and '''T''' keys simultaneously on your keyboard.

|On the '''Terminal ''' type,'''ls space asterix dot sh''' press '''Enter.'''

|It matches all the files having '''.sh extension''' in the present directory.

|Here we can see that all the '''sh''' files are listed.

|Let me clear the prompt,Now type, '''ls space s asterix dot sh''' press '''Enter.'''

| We can see that '''s asterix dot sh''' matches all the files starting with character '''s''' and having '''sh as  extension.  

| Lets move on ,

| Now type, '''ls space opening square bracket a hyphen c closing square bracket asterix dot sh''' press '''Enter.'''

| This will match and display the files starting with letter ''' a''' or '''b '''or '''c.'''

| Observe the output.

|We see a list of all files starting with character ''' a '''or '''b''' or '''c.'''

|Now, let's go ahead and type '''ls space opening square bracket caret sign a hyphen c closing square bracket asterix dot sh''' press '''Enter.'''

| This will match all the filenames with '''extension''' '''sh.'''  

|But will omit those starting with character as ''''a'''' OR ''''b'''' OR ''''c''''

| Observe the output. You will notice that the filenames are not starting with character ''''a'''' , ''''b'''' or ''''c''''.

|Let me clear the prompt,

| Now type, '''ls space opening square bracket capital 'A'  small 'a' closing square bracket asterix sign dot sh''' press '''Enter.'''

| This will match filenames starting with upper and lower case of letter ''''A''''.

| See the output.All filenames starting with upper and lower case ''''A''' and extension '''sh''' are listed.

| Switch to the slides.

| '''Export command''' Exports a '''variable''' or a '''function''' to the '''environment''' of all '''child processes'''.

| Switch to the '''Terminal ''' type, '''myvar equal to sign lion''' press''' Enter.'''

| Now type, '''echo space dollar sign myvar''' press '''Enter.'''

| To go to a new '''Shell''', we can either open a new '''Terminal''' or type, '''slash bin slash bash''' press''' Enter.'''

| Type, '''echo space dollar sign myvar''' press '''Enter.'''

| Type, '''export space myvar equal to sign lion ''' press''' Enter.'''

| Now type, '''echo space dollar sign myvar''' press '''Enter.'''

| Let's navigate to another '''Shell''', type, '''slash bin slash bash''' press ''' Enter.'''

|  Now type,'''echo space dollar sign myvar'''.  

| This is because we have declared the variable '''myvar''' globally using the export command.

| Let us summarize. Come back to our slides.

|  In this tutorial we learnt,

|* '''Export command'''

| As an assignment.

| Watch the video available at the link shown below

| It summarises the Spoken Tutorial project  

| If you do not have good bandwidth, you can download and watch it

|The Spoken Tutorial Project Team

| Conducts workshops using spoken tutorials  

| Gives certificates to those who pass an online test  

|Spoken Tutorial Project is a part of the Talk to a Teacher project

| It is supported by the National Mission on Education through ICT, MHRD, Government of India

|More information on this Mission is available at the link shown below.

| This is Ashwini from IIT Bombay Signning off.