Hello,
I need to insert a line (like a header) as the first line of a very huge file (about 3 ml rows). I am able to do it with sed, but redirecting the output and creating a new file takes quite some time. I was wondering if there was a more efficient way of doing it?
Any help would be... (3 Replies)
folks,
In my working directory, there a multiple large files which only contain one line in the file. The line is too long to use "grep", so any help?
For example, if I want to find if these files contain a string like "93849", what command I should use?
Also, there is oder_id number... (1 Reply)
Hi,
I have a huge file of bibliographic records in some standard format.I need a script to do some repeatable task as follows:
1. Needs to create folders as the strings starts with "item_*" from the input file
2. Create a file "contents" in each folders having "license.txt(tab... (5 Replies)
hi all,
In an mp3 file , data is arranged in sequence of header and data ,how to retrieve data between two headers. Is the data between two headers fixed? because as per theory it says 1152 samples will be there , but dont knw how many bits one sample correspond to?
it would help if any c... (2 Replies)
I’m new to Linux script and not sure how to filter out bad records from huge flat files (over 1.3GB each). The delimiter is a semi colon “;”
Here is the sample of 5 lines in the file:
Name1;phone1;address1;city1;state1;zipcode1
Name2;phone2;address2;city2;state2;zipcode2;comment... (7 Replies)
Hi, Great minds, I have some files, in fact header files, of CTD profiler, I tried a lot C programming, could not get output as I was expected, because my programming skills are very poor, finally, joined unix forum with the hope that, I may get what I want, from you people,
Here I have attached... (17 Replies)
I'm trying to take mrt output and put it at the top of a file along with the date and time. I was able to do it at the bottom of the file with the following
printf "********** $(date) **********\n\n" >> $OUTPUT_PATH/$HOSTNAME
mtr -r -w -c 10 $HOSTADDRESS >> $OUTPUT_PATH/$HOSTNAME
printf... (2 Replies)
Optimization shell/awk script to aggregate (sum) for all the columns of Huge data file
File delimiter "|"
Need to have Sum of all columns, with column number : aggregation (summation) for each column
File not having the header
Like below -
Column 1 "Total
Column 2 : "Total
...
...... (2 Replies)
I have 2 large file (.dat) around 70 g, 12 columns but the data not sorted in both the files.. need your inputs in giving the best optimized method/command to achieve this and redirect the not macthing lines to the thrid file ( diff.dat)
File 1 - 15 columns
File 2 - 15 columns
Data is... (9 Replies)
Discussion started by: kartikirans
9 Replies
LEARN ABOUT HPUX
stdio
stdio(3S)stdio(3S)NAME
stdio() - standard buffered input/output stream file package
SYNOPSIS DESCRIPTION
The Standard I/O functions described in the subsection(3S) entries of this manual constitute an efficient, user-level I/O buffering
scheme. The and functions handle characters quickly. The following functions all use or act as if they use and and can be freely inter-
mixed:
A file with associated buffering is called a stream and is declared to be a pointer to a defined type creates certain descriptive data for
a stream and returns a pointer to designate the stream in all further transactions. Section(3S) library routines operate on this stream.
At program startup, three streams, and are predefined and do not need to be explicitly opened. When opened, the standard input and stan-
dard output streams are fully buffered if the output refers to a file and line-buffered if the output refers to a terminal. The standard
error output stream is by default unbuffered. These three streams have the following constant pointers declared in the header file :
standard input file
standard output file
standard error file
A constant, NULL, (0) designates a nonexistent pointer.
An integer-constant, (-1) is returned upon end-of-file or error by most integer functions that deal with streams (see individual descrip-
tions for details).
An integer constant specifies the size of the buffers used by the particular implementation (see setbuf(3S)).
Any program that uses this package must include the header file of pertinent macro definitions as follows:
The functions and constants mentioned in subsection(3S) entries of this manual are declared in that header file and need no further decla-
ration.
A constant defines the default maximum number of open files allowed per process. To increase the open file limit beyond this default
value, see getrlimit(2).
WARNINGS
Use of interfaces with a shared read/write file descriptor on will provide undefined behavior. Applications which are doing operations on
need to use seperate file pointers for input and output, even if using the same file descriptor for both types of operations.
ERRORS
Invalid stream pointers usually cause grave disorder, possibly including program termination. Individual function descriptions describe
the possible error conditions.
SEE ALSO close(2), lseek(2), open(2), pipe(2), read(2), getrlimit(2), write(2), ctermid(3S), cuserid(3S), fclose(3S), ferror(3S), fgetpos(3S),
fileno(3S), fopen(3S), fread(3S), fseek(3S), fgetpos(3S), getc(3S), gets(3S), popen(3S), printf(3S), putc(3S), puts(3S), scanf(3S), set-
buf(3S), system(3S), tmpfile(3S), tmpnam(3S), ungetc(3S).
STANDARDS CONFORMANCE stdio(3S)