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Assuming that we have entered John, Jean-Francois and Yoko as the 3 names, myfile.txt would contain:

Name 1 [John ]
Name 2 [Jean-Franc]
Name 3 [Yoko ]

The fputc() function prototype is as follows.

int fputc(int character, FILE *fp);

The fputc() function writes a character to the file associated with fp. The character is written at the current position of the fp as indicated by the internal position indicator, which is then advanced one character

Return value: If there are no errors, the same character that has been written is returned.If an error occurs, EOF is returned and the error indicator is set.

Write the program that creates a file called alphabet.txt and writes ABCDEFGHIJKLMNOPQRSTUVWXYZ to it.

#include<stdio.h>int main () {FILE * fp; char c;fp = fopen ("alphabet.txt","w"); if (fp!=NULL){ for (c = 'A' ; c<= 'Z' ; c++) {fputc ((int) c , fp); }fclose (fp); }return 0; }
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The fputs() function prototype is as follows.

int fputs(char *str,FILE *fp);

The fputs() function writes the string pointed to by str to the file associated with fp.

Return value: On success, a non-negative value is returned. On error, the function returns EOF. The null that terminates str is not written and it does not automatically append a carriage return/linefeed sequence.

Write the program allows to append a line to a file called myfile.txt each time it is run.

#include<stdio.h>int main () {FILE * fp; char name [50]; puts ("Please, enter a name: ");gets (name); fp = fopen ("myfile.txt","a");fputs (name,fp); fclose (fp);return 0; }
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Read data from text files

When reading data from text files, C provides three functions: fscanf() , fgetc() , fgets() .

The fscanf() function prototype is as follows.

int fscanf(FILE *fp, char *format, ...);

This function reads data from the file specified by file pointer fp and stores them according to the parameter format into the locations pointed by the additional arguments. The additional arguments should point to already allocated objects of the type specified by their corresponding format tag within the format string.

Return value: On success, the function returns the number of items successfully read. This count can match the expected number of readings or be less -even zero- in the case of a matching failure. In the case of an input failure before any data could be successfully read, EOF is returned.

Read an integer number and a character from file associated with a file pointer fp and stores them to two variables a and c.

fscanf(fp, "%d %c",&a,&c);
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#include<stdio.h>int main () {char str [80];float f; FILE * fp;fp = fopen ("myfile.txt","w+"); fprintf (fp, "%f %s", 3.1416, "PI");rewind (fp); fscanf (fp, "%f",&f); fscanf (fp, "%s", str);fclose (fp); printf ("I have read: %f and %s \n",f,str);return 0; }
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This sample code creates a file called myfile.txt and writes a float number and a string to it. Then, the stream is rewinded and both values are read with fscanf. It finally produces an output similar to:

I have read: 3.141600 and PI

Questions & Answers

do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
characteristics of micro business
Do somebody tell me a best nano engineering book for beginners?
s. Reply
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
what is the actual application of fullerenes nowadays?
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
is Bucky paper clear?
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Do you know which machine is used to that process?
how to fabricate graphene ink ?
for screen printed electrodes ?
What is lattice structure?
s. Reply
of graphene you mean?
or in general
in general
Graphene has a hexagonal structure
On having this app for quite a bit time, Haven't realised there's a chat room in it.
what is biological synthesis of nanoparticles
Sanket Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
many many of nanotubes
what is the k.e before it land
what is the function of carbon nanotubes?
I'm interested in nanotube
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
what is nano technology
Sravani Reply
what is system testing?
preparation of nanomaterial
Victor Reply
Yes, Nanotechnology has a very fast field of applications and their is always something new to do with it...
Himanshu Reply
good afternoon madam
what is system testing
what is the application of nanotechnology?
In this morden time nanotechnology used in many field . 1-Electronics-manufacturad IC ,RAM,MRAM,solar panel etc 2-Helth and Medical-Nanomedicine,Drug Dilivery for cancer treatment etc 3- Atomobile -MEMS, Coating on car etc. and may other field for details you can check at Google
anybody can imagine what will be happen after 100 years from now in nano tech world
after 100 year this will be not nanotechnology maybe this technology name will be change . maybe aftet 100 year . we work on electron lable practically about its properties and behaviour by the different instruments
name doesn't matter , whatever it will be change... I'm taking about effect on circumstances of the microscopic world
how hard could it be to apply nanotechnology against viral infections such HIV or Ebola?
silver nanoparticles could handle the job?
not now but maybe in future only AgNP maybe any other nanomaterials
I'm interested in Nanotube
this technology will not going on for the long time , so I'm thinking about femtotechnology 10^-15
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Introduction to computer science. OpenStax CNX. Jul 29, 2009 Download for free at http://cnx.org/content/col10776/1.1
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