pupuboo
asked on
How to use sscanf
Hi ,
I need to read in a txt file with below syntax:
#
# This is text file:
#
# color : number : exist : [OLD_STUFF]
#
PRODUCT: abc
orange : 230 : 1,4,6,8,11,44-67,88
purple : 127 : 3,9,22,55-77,99 : OLD_STUFF
PRODUCT: xyz
white : 230 : 1,4,6,8,11,88
black : 130 : 3,9,22,99 : OLD_STUFF
blue : 679 : 0-11, 100-237, 239
1. how to write sscanf to read in a file that generic enough,
if see "#" , no process
no "#", further process
2. if further process.
how to write generic sscanf to read data from "orange : 230 : 1,4,6,8,11,44-67,88" and "black : 130 : 3,9,22,99 : OLD_STUFF"
I need to read in a txt file with below syntax:
#
# This is text file:
#
# color : number : exist : [OLD_STUFF]
#
PRODUCT: abc
orange : 230 : 1,4,6,8,11,44-67,88
purple : 127 : 3,9,22,55-77,99 : OLD_STUFF
PRODUCT: xyz
white : 230 : 1,4,6,8,11,88
black : 130 : 3,9,22,99 : OLD_STUFF
blue : 679 : 0-11, 100-237, 239
1. how to write sscanf to read in a file that generic enough,
if see "#" , no process
no "#", further process
2. if further process.
how to write generic sscanf to read data from "orange : 230 : 1,4,6,8,11,44-67,88" and "black : 130 : 3,9,22,99 : OLD_STUFF"
ASKER CERTIFIED SOLUTION
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btw are you sure you have to use sscanf ? cos sscanf cannot read directlyfrom a file .. its reads only from a buffer .
I think reading the line first and then deciding how to process is probably cleaner - certainly more flexible, but if you really want to scanf...
The following code produces this output:
Color: orange, #230, 1,4,6,8,11,44-67,88
Color: purple, #127, 3,9,22,55-77,99, OLD_STUFF
Color: white, #230, 1,4,6,8,11,88
Color: black, #130, 3,9,22,99, OLD_STUFF
Color: blue, #679, 0-11,
--------------------------
FILE *stream = fopen(filename, "r");
char color[32], exist[32], stuff[32];
long number;
int numFields = 0;
while ( (numFields = fscanf(stream, "%s : %d : %s :%s", color, &number, exist, stuff)) > 0)
{
if ( numFields > 1 )
{
std::cout << "Color: " << color << ", #" << number << ", " << exist;
if ( numFields > 3 ) std::cout << ", " << stuff;
std::cout << std::endl;
}
}
The following code produces this output:
Color: orange, #230, 1,4,6,8,11,44-67,88
Color: purple, #127, 3,9,22,55-77,99, OLD_STUFF
Color: white, #230, 1,4,6,8,11,88
Color: black, #130, 3,9,22,99, OLD_STUFF
Color: blue, #679, 0-11,
--------------------------
FILE *stream = fopen(filename, "r");
char color[32], exist[32], stuff[32];
long number;
int numFields = 0;
while ( (numFields = fscanf(stream, "%s : %d : %s :%s", color, &number, exist, stuff)) > 0)
{
if ( numFields > 1 )
{
std::cout << "Color: " << color << ", #" << number << ", " << exist;
if ( numFields > 3 ) std::cout << ", " << stuff;
std::cout << std::endl;
}
}
You should note that the fscanf is fragile. If the input lines are not all formatted alike, it won't work.
SOLUTION
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SOLUTION
membership
This solution is only available to members.
To access this solution, you must be a member of Experts Exchange.
SOLUTION
membership
This solution is only available to members.
To access this solution, you must be a member of Experts Exchange.