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Top Forums UNIX for Dummies Questions & Answers Meaning of script with echo, -d, -f1, -f2 Post 302889357 by bakunin on Thursday 20th of February 2014 05:42:07 AM
Old 02-20-2014
Quote:
Originally Posted by DK2014
Is there any online link or PDF file where I can find the meaning of below,
Much better: there is a command and a database on every UNIX system: "man". If you need information about "command", enter "man command" and this should bring up a general description and all the possible options and arguments for "command", along with some example usages.

To answer your question partly:

"cut" gets some input stream and extracts a certain piece, which it outputs:

Code:
<input stream> | cut <options> | <part of the input stream cut out>

The used options and arguments tell you how the input stream is cut:

"-d<character>" means "use this character as the field delimiter". Consider the input stream:

"ab:cd:ef:gh"

"cut -d:" would now mean that ":" is used to split the stream into pieces.

"-f<number>" means to extract the field with the number after splitting the stream into pieces. Using the above stream

Code:
echo "ab:cd:ef:gh" | cut -d: -f1

would yield "ab" (the first "field"), while

Code:
echo "ab:cd:ef:gh" | cut -d: -f3

would yield "ef". Now, compare this explanation with the content of "man cut" (and all the other commands you wanted to know) and you will see that i would have to write a whole lot of text to come close to the precision of these explanations.

Some hints, though:

"[ ...]": look under "man test". Why this is so has historical reasons.

"while", "read": internal shell commands, they do not have a man page of their own. see under "man ksh" and "reserved words".

I hope this helps.

bakunin
 

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IGNORE_USER_ABORT(3)							 1						      IGNORE_USER_ABORT(3)

ignore_user_abort - Set whether a client disconnect should abort script execution

SYNOPSIS
int ignore_user_abort ([string $value]) DESCRIPTION
Sets whether a client disconnect should cause a script to be aborted. When running PHP as a command line script, and the script's tty goes away without the script being terminated then the script will die the next time it tries to write anything, unless $value is set to TRUE PARAMETERS
o $value - If set, this function will set the ignore_user_abort ini setting to the given $value. If not, this function will only return the previous setting without changing it. RETURN VALUES
Returns the previous setting, as an integer. EXAMPLES
Example #1 A ignore_user_abort(3) example <?php // Ignore user aborts and allow the script // to run forever ignore_user_abort(true); set_time_limit(0); echo 'Testing connection handling in PHP'; // Run a pointless loop that sometime // hopefully will make us click away from // page or click the "Stop" button. while(1) { // Did the connection fail? if(connection_status() != CONNECTION_NORMAL) { break; } // Sleep for 10 seconds sleep(10); } // If this is reached, then the 'break' // was triggered from inside the while loop // So here we can log, or perform any other tasks // we need without actually being dependent on the // browser. ?> NOTES
PHP will not detect that the user has aborted the connection until an attempt is made to send information to the client. Simply using an echo statement does not guarantee that information is sent, see flush(3). SEE ALSO
connection_aborted(3), connection_status(3), Connection Handling for a complete description of connection handling in PHP. . PHP Documentation Group IGNORE_USER_ABORT(3)
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